I owned a 1995 R33 GTS-t for 2.5yrs, 5wks ago I bought a 1994 R32 GTR. From my personal opinion the GTS-t is absolutely no match compared to the GTR in any way (driving, looks, performance etc).
The R33 GTS-t is certainly the weekend cruise car, nice comfortable soft ride, enough room for 4 blokes, decent power options, etc. The GTR is more the weekend trackday warrior. Power is easily obtained, the handling is 100x better and it looks 100x better too.
As for costs (GTS-t vs GTR) i'm still of the opinion that they are basically identical in general running costs. It's not until you starting blowing engines or gearboxes where the costs would be more for the GTR, but then again a rebuild of an engine/gearbox is a rebuild and it costs money no matter what type of car you have. I've created a thread with a 'my running costs experience' thread which you can view here: here
My advice would be to spend as much as you can on the purchase of the vehicle as generally it will be a better quality car. Something in the high 20's for an R32 and high 30's for an R33 should be ok.