Now here's an excellent example of an affordable, yet high performing in-dash navigation. The Power Acoustik PAVN-4210 is a single DIN head unit that has built-in navigation. The PAVN-4210 is Power Acoustik's answer to the increasing demand for vehicle navigation devices.

Display
First off, the front panel is slightly larger than a standard single DIN size mounting. This may be a problem for those with limited mounting space on their dashboard console. However, it does feature a large 4.3" LCD touchscreen monitor that is both bright and attractive to the eyes. A typical single DIN receiver features a maximum 3" LCD display, unless it is a retractable, flip-out type which could typically house a 7" LCD screen. The 4.3" LCD display is a nice feature to have, since it makes the unit unique as well as versatile. It could even drop to three different positions to accommodate for better viewing angle.

Compatibility Features
The PAVN-4210 is capable of playing common media formats such as MP3, MP4, and standard DVD/DVD-R/RW. But it could also play DivX file formats; all of which could be displayed as NTSC or PAL color system for greater compatibility. This means that the unit could play display video from virtually any country of origin where NTSC or PAL is the standard color system.

Expandability Options
This versatile unit is also capable of receiving (with additional accessories) Satellite Radio (both XM and Sirius). Satellite Radio information will be displayed on the screen which would display station information and current program. In addition, this in-dash navigation multimedia receiver features a mini USB port as well as an SD Card input, allowing users to play their favorite MP3 or MP4 files or even update their navigation maps.

Navigation Features
The unit comes with a 2GB SD Card with map information as well as 7 million points of interest. The internal processor is a 400 MHz Sirf Star III chip running a Linux-based software. This means that users will not experience much lag or sluggish performance while navigating and calculating routes while driving. The GPS receiver is even capable of receiving 20 parallel channels, allowing connection of up to 20 orbital GPS satellites which greatly reduces the likelihood of signal loss while traveling long distances. The GPS receiver will also receive signals from traffic alerts, notifying you of accidents as well as traffic status in major US metropolitan cities.

As you can probably gather from what is covered in this review, this affordable single DIN in-dash navigation is packed with features that are usually reserved for more expensive units. However, for the price that is offered ($429.99), you can't get a better deal than the Power Acoustik PAVN-4210.

Introducing the Kenwood DNX-5120, this in-dash navigation and multimedia receiver is both attractive and versatile in performance. It features a large double DIN 6.1" LCD touchscreen with a disc slot insert right above the monitor.

Display
Let's go over some of its features and I will ensure you that you will not think twice about getting one of these. The first advantage of the unit is the large 6.1" touchscreen. A typical portable navigation device features a screen that is 3.5" to as large as 4.3" touchscreen. The decisive advantage here is the 2" bigger screen than an ordinary portable GPS device. This will allow for greater visibility as well as a more enjoyable media playback, such as DVD playback or image viewing.

Compatibility
This receiver is compatible with most media files that you are probably accustomed to. It will play your favorite DVDs and of course CDs. However, it will also play MP3s and WMAs that you had recently downloaded, but not only that, it is also capable of playing Apple iTune's AAC file formats. The DNX-5120 could even play the much rarer DivX and VCD file formats as well as image viewing of JPEG files.

Audio Features
How would you like to experience home theater in your car? Well now you can! This multimedia receiver is capable of Dolby Digital playback, allowing you to enjoy a surround sound experience with support for a center channel and subwoofer channel outputs.

Expandability Options
Kenwood's DNX-5120 has virtually limitless expandability options as it is Satellite and HD Radio ready, iPod ready, and even Bluetooth ready. It also features a 3.5mm front auxiliary input, allowing users to plug in any device with a headphone jack output. In addition, it has a rear USB and additional RCA audio/video inputs, giving the unit plenty of options for media playback and source expansions.

Navigation Features
The built-in GPS navigation features 6 million points of interest. The internal software is actually Garmin designed, so you can be sure that your navigation will always be accurate and quick to respond.

With the amount of features that the unit has to offer, it would not be surprising to see this double DIN in-dash navigation receiver to be one of the top competitors in its category this year. The bigger Kenwood DNX-7120, features similar functions and compatibility but has a 6.95" (virtually 7") screen rather than the 6.1" touchscreen. The DNX-7120 also fills up the entire face with its touchscreen and has its DVD insert slot hidden behind the screen.

This is arguably the crown jewel of portable navigation. Of course, you can't really expect anything less from a top tier company like Harman Kardon. The Harman Kardon GPS-810 features an incredibly thin casing, with a width measuring no more than ¾" thick. With this kind of style, you'll definitely impress your friends with how good your dashboard will look after you mount one of these.

Display Features
It features a very bright and daylight-readable 4.3" LCD display, capable of down-scaling pictures as large as 4096 x 3072 pixels. The built-in GPS system is capable of displaying US, Puerto Rico, and Canada maps without additional mediums such as a disc or a flash card. In addition, it features a blazing fast 532 MHz i.MX31L processor. The combination of the two will give users quick response and calculations from starting point to destination. You can be sure that the unit will also have a fast refresh rate so that you won't see much lag at all when navigating through high speed freeways.

Navigation Features
Where typical GPS navigation have 1 to 6 million points of interest, the GPS-810 features an internal memory that holds over 12 million points of interest. With the vast amount of locations stored internally, you are most likely to find the most current directional and address guides to your favorite landmarks, restaurants, and of course, gas stations. What is amazing is the unit's 16-channel GPS receiver (which is by the way capable of receiving traffic messages). The 16-channel receiver could lock on to 16 different orbital GPS satellites and makes sure that you won't lose reception where ever you are.

Compatibility
This portable unit is also capable of playing music files in AAC, MP3, WMA, WMV, and WMA with WM-DRM10 (Digital Rights Management) format. In addition, it will display album art and you could play music while you're navigating. I know what you may be thinking. You're thinking "why would I want to play music through the small built-in tin-can speakers?" But instead you could use its included FM modulator or its 3.5mm auxiliary output, and you would be able to hear digital quality music through your existing audio system. Moreover, if you insert an SD Card, the unit is capable of file transfers from your computer through the USB connection.

Bluetooth Features
The GPS-810 also features a built-in Bluetooth connection that displays caller ID and call status on the 4.3" LCD display. This will allow you to communicate through either its built-in audio or through your car's audio system with either the FM or auxiliary connection. It could even synchronize your cell phone's phonebook and will display any contact information on the screen for easy-to-navigation access.

Wireless Remote
To top it all off, the Harman Kardon GPS-810 includes a wireless remote. This is my favorite feature because it does not force me to lean over or reach forward to access the unit. Instead it's sensitive and easy-to-use remote is very familiar to use and could even be mounted anywhere it is convenient for you such as the center console or your door-side arm rest console.

With such great features, this Harman Kardon unit stands as one of the best GPS portable navigation unit as of first quarter 2008. It's going to be tough finding similarly featured as well as similarly performing competitors, especially with a price tag of less than $400, this premium quality navigation unit. It's worth every penny and you won't ever regret your purchase!