Hey,
I have just swapped over from a 180sx that has an unlimited list of aftermarket goodies available to an R34 and I was quite suprised the lack of available parts and options for the 34, sure you can get alot of parts but there isn't much variety if you know what I mean.
But on the other hand I have found they respond very well to mods.
The only let down is the turbo, but there is a sponsor on here that does a Hi-Flow version quite cheap.
As you stated it all realy depends on one's budget.
Hope this helps
Cheers
Josh