Hah, Pretty much because I can see good reason in both points of view.
I've love the lightness and cheapness of the S13 and there is something to be said for going along to a track day and being just .2 of a second off an M5 that's only a couple of years old, we all know it's a super heavy GT style car but it's expensive and it's got power so I got a buzz from that. At the same time he got in that M5 and cruised home like he'd been out for a Sunday drive, gotta appreciate that.
On the other hand, I loved my GT-R but part of that was that I'd bought it modified and didn't have it quite long enough to ever have any major dramas with it, that and it was only mild tune 250awkw so not heaps should go wrong at that power. Sure I had to put some AFM's on it, common issue, and the parts cost for service items weren't awesome (because I wanted to treat it right). But the fun I had on the track tangling with much lesser powered WRX's coupled with driving it to work from time to time just to hear it scream down the on ramp was hard to match, I don't get that same feeling from the Silvia but it's a "dirty track car". At the same time, pulling into the pits, I thought, how the hell does a 2000 model WRX with only 160-170awkw keep up with my car on the straights. I've got 2 more cylinders, an extra turbo and this car new cost literally 3 times as much as the WRX. The answer of course is weight. My car wasn't that much more expensive than his at the time so it wasn't too bad and I did over take him so I at least felt justified in my GT-R ownership.
It really is a tough one and when the time comes it will likely depend on what's around, what frame of mind I'm in and how much money I have to play with. No doubt the S14 option is much cheaper in basically every way, but It's not the sort of car I see myself taking for a weekend cruise so it should be cheaper as it'll be performing one less function for me. Some people might not get that but with the exception of the S15, I don't see Silvia's as great streeters, they're a bit small and a bit coarse. That's a personal thing though as I've taken my antics off the street now so I don't want something quite so raw for sunday cruising.