I had some seat time on a TZ 250 Tigger and I don't think I can make a 370 lb bike handle like a 286 or whatever bike does...90 lbs is an incredible difference in braking and turning. I think even the AMA superbikes weigh more than 370 lbs. And then their is the difference in engine/crankshaft mass...Just no way to replicate it on a budget.
On the other hand your right, 4 strokes are so much better with maintenance there isn't a comparison at all. They are pretty great.
So on an ulimited budget, sure we build a bare bones titanium framed GSXR1000 with ultra light forks and wheels. Everything lightened. Or we spend the same amount and buy this 500...