If pure acceleration is all you're after though, by all means, go for the R1.
But if you want to really learn the craft and hone your skills, an SV650 or something like that will make a much better learning tool.
That's assuming you haven't got much track time under your belt yet. If you do, forgive me. Either way, it's your call... just trying to pass on some experienced wisdom.
I do about 10-12 track days plus 8 race weekends per year, been racing & instructing since '06.
But getting back to bike selection, I've ridden EX500's, Motards, 600's, Ducati's, even an MV Agusta F4 on the track... The big bikes were definitely a thrill, no doubt about it, but a smaller bikes inspire so much more confidence and teach you so much so fast. The feeling you get when you start learning to ride a lightweight near its limit & you're passing other riders on superbikes... you just can't be beat it.
Not only that, but the lightweights are a lot cheaper, too. You can get a race ready SV650 for under 4 grand & your tires will last two or three times as long as they would on an R1, plus a 160 rear is cheaper than a 180 or 190... at upwards of 200-250 bucks each, that's a significant savings. You can buy a lot more track time with the money you save just on tires alone.
So yeah, the R1 would be a rush and the lightweights aren't as fast or as glamorous, but something like an SV is far more economical, a better learning tool and is quite possibly more satisfying to ride.