Stock for stock, the 34 is nowhere near the level of a 35.
The 35 is also the only car that has put a smile on my face without a clutch pedal, going from 35 back to an rb model you really feel the age of the 'old' gtr's.
For reference a stock 35 gtr does tsukuba in same time as z tune 34, which is regarded as the best goin street 34.
34 wins on price an maintenance though, unless u do it up you will not have maintenance costs like u see from r35.
For everything else, but pointless back seats, the 35 wins imo. So easy to drive, so fast, no lag, torque in any gear ( an amount you can only dream of from a rb ) great handling etc.
If money is not a problem I'd pick a r35 if I was you, the hype on them is well justified!!!