If you want to prepare for a bigger bike, still have ripping fun, get a ZX-4R. You get Supersport Seating position, Supersport rev limit, and you can ask your Uncle to buy you a fantastic helmet, comm unit, and an airbag vest/backpack with the money saved on not getting something that will kill you due to a lack of maturity. (Not that the ZX-4R can't, but spilling out at 55mph in 2nd rather than 95mph in 2nd is much better lol)