I own both so...
I have owned my 1993 RX7 for over a year. Drove it as hard as any sports car and it's been modified with intake, intercooler, DP, midpipe w/cat, exhaust, gauges etc. - stock boost. It'll hang with a C5 Corvette on the highway and is lighter\better handling than the Supra. NO ENGINE PROBLEMS. The motor had supposedly been replaced twice on it before I bought it because the first owner was a fool who kept turning the boost WAY up. RX7 do NOT like detonation and that's exactly what happened to the motor with that much boost. I on the other hand didn't screw with the boost and it run s GREAT. Unfortunatly the clutch was less happy about it and needs replacing.
Having said that - the car is for sale and a Supra is replacing it. The RX7 handles better IMO and it gets boost MUCH quicker (2K it has usable boost!). It also loves high RPM more than the Supra. But I wanted MORE power. There are NOT many people I would trust hopping up an RX7, certainly not some grease monkey. The Supra has an engine that is more forgiving. The car weighs more, costs more, but in the end I'm confident I can get the power I want out of it with less chance of blowing it up. I simply didn't wish to risk the RX7 - it's an awesome car that looks great, I didn't want to trash it.
If you take care of it, change the oil regularly, don't overheat it, and don't get stupid the RX7 is a fine car. The folks who say they blow up every 4days haven't owned one or are just parroting B.S. they heard from a friend of a friend. Sorry guys, it has to be taken care of like any other car

It'll cost less to buy, mine is selling for $17K OBO and it's far from stock. The Supra cost me a good $10K more (shrug). Insurance is less on the RX7 too for some reason but it sure "looks" like a faster car

The Supra would STOMP it though. Driving an RX7 is a different feeling, lot's of revs and when the second turbo comes on you really start moving on a modified car. It's almost an apples\oranges comparison - the Supra is bigger and more comfortable etc..
RX7
Supra
Weird, pics aren't showing up?! Used to work...