Like pretty much said, unless it's a GTR go for the Z32. I just sold my TT Zed after 6 years, great car. Plenty of power, same weight as a GTR but unfortunately only RWD. With 300hp at the wheels mine found it hard to get the power down. I truly wouldn't be worried about a targa, they are slightly heavier than the non-targas which is extra strengthening in the roof. I never noticed much body flex at all, my car previous to the Zed had heaps. It would even lift up a tyre coming into my driveway sometimes which to me indicates bugger all flex.
Yeah they are a prick to work on, but it just involved removing stuff in the way before you got to what you needed! I did all the work on it myself including several plenum pulls and it just took time. Very reliable car, I'd heard horror stories before I bought it but like all performance cars if you don't maintain them they will break. Worst thing that happened to mine was the odd coolant leak which when replaced with silicone hoses isn't an issue. It pays to upgrade the radiator though, there's a lot of engine squeezed into that engine bay. There is a lot of shit unmaintained ones around bought by people who just wanted them for their looks so make sure you do your homework and buy a good one.
Cheers,
Matt