I've gone back and forth from a Ti 4200 on an AMD CPU rig, to the X800XT and X1950Pro on an Intel P4 rig, to a GTS 250 then my current HD7970 on my latest i7 950 rig.
The X800XT and X1950Pro series had their driver pains, and I was a bit miffed that the X1950Pro shortly after getting it was relegated to Legacy driver support. That's partly me buying very late in the model cycle, but it's worth mentioning that others with just as old if not older Nvidia GPUs at the time were not having problems with driver support. With Nvidia it wasn't so much about individualized software support as their older GPU architecture being more compatible than ATI's was with newer drivers I think. So you got more trouble free life out of them.
Lately though, as mentioned, AMD's drivers are just as good, sometimes depending on the game, even better at launch than Nvidia's. When I first got my 7970, AMD was releasing new drivers like candy every 1 to 3 months. Now they release less often and usually only include support for the newest GPUs or APUs, or have Crossfire performance gains on certain games.
What worries me is with AMD's tight budget and recent HUGE staff cuts, this focus on new GPUs and Crossfire has them neglecting to look for performance gains and driver fixes with older model single GPU performance, even on major titles.
On capture support, ShadowPlay is ahead of Raptr's Game DVR on features and performance, but Game DVR is still in beta. One of the key differences is Game DVR can record only half the chached gameplay of ShadowPlay's 20 minutes, and let's face it, the caching is THE unique and convenient feature in these tools.