The problem with a R34 GTT is you'll spend most of the time looking at it and wishing it looked like the GTR.
You could put a GTR nose, wing, and skirts on it, bit you'd be lying to yourself and it's a waste of money in the end.
Having said that, I'd still have the GTT over the R33 GTR.
I'm at the point where I'm looking at replacements for the Z32 at the end of the year, and it's either going to be a C5 Corvette or a R34 GTT.