There are a number of good reasons to use a hanging tomato planter.

Location
You can put them almost anywhere. Try a balcony, the patio, or even your front porch. With a hanging planter, you have much more flexibility.

Air Circulation
By hanging in the air, the improved air circulation not only avoids problems with many diseases, but yields are improved with better pollination.

Staking
In a word, none. You don't need to stake, at most you may need to prune occasionally.

Soil
Since you are filling a container, you can make the soil as good as you want. Add lots of organic compost or other amendments, and fertilize appropriately. Since you can replace the soil annually, there are fewer diseases to deal with as well.

There's more, but you get the idea. Hanging tomato planters are great.

So what's the story with upside down hanging tomato planters. What's the best way grow hanging tomatoes?

It turns out there are a couple of commercially available planters to do this. One very popular planter is the Topsy Turvy planter. This is designed to hold a single plant. If you are interested in more than one tomato plant, you might consider either the Topsy Turvy Tomato Tree, or an even more capable version is the Upside Down Tomato Garden, which holds more than one tomato plant and other herbs and vegetables as well.

Topsy Turvy Planter

It was once featured in Time magazine. It basically holds one plant, although some people will try 2 plants (one in the hole on the top, another in the normal hole on the bottom). You get the plant started by growing it right side up, and then mount it upside down.

Why do this? With upside down tomatoes you have no problems with slugs. It's well covered and won't need to water very often. Usually you don't stake the plants, as the branches will fall on their own.

You can also use one to grow other small bush type plants like peppers and eggplants. You can use several for more than one type of vegetable or herb.

Mounting it is the biggest problem. It can get quite heavy, especially after you've watered. If you are trying to move a fully loaded plant it can be difficult.

Overall this novel approach can work well for your tomato growing needs

Upside Down Tomato Garden by Hammacher Schlemmer

A heavy duty version of the upside down planter. It has a platform that can handle many more plants. In addition to 4 tomato plants, it will hold smaller flowers and herbs in the top platform of the planter. Or you may use the multiple slots to grow peppers and eggplant instead of only tomatoes. The supporting stand is part for the unit and it holds the garden at the right height.

This unit can be placed in many more locations, and you don't have to craft a support unit or hang it from some other structure. It's attractive enough that you can put it on the deck or patio, or a location that's convenient from your kitchen.

The Tomato Garden is the sturdier solution than a simple hanging tomato planter, will be more productive overall, and is more flexible in where you put it. The Topsy Turvy is a nice starter unit, and may work better in smaller settings like an apartment patio. Either one can be a good choice to start your tomato growing needs.