This is our first time trying it. We had an extra plant so we stuck it on top. So far so good. Both plants are thriving (even though they got beat up by the windstorm last week) and they're starting to produce nice fruit. One cool thing about it is that when you water it (or when the drip turns on) the excess water flows out of the bottom. This doesn't seem to hurt the plants and their roots seem to get plenty of moisture. We catch the excess water in a bucket and use it to water other plants.
I tried the Topsy-Turvy planters for the past two summers, but didn’t get anything out side of root-rot for the plants in the bottom. Lat year, I planted pepper in the top, but they were still affected by the heat and didn’t grow well.