in the 28k range, you can get almost every bike in the second hand market, BUT, the question is which one will you be comfortable with?
im not with TNT getting a 954RR for urself,id say go slow, n ull go far...if u jump too fast u wont last!
n the brain of an 18 year old and a 1000cc roaring to your command its surely a deadly combo...thats the only reason i dint get a 1000...no matter hw self controlled you are, you tend to lose it sometimes...
since youve already have had some time on a 250, i wouldnt say go for a 400 but instead get a 600 and trust me, the 600s have enough potential to keep you happy for maybe the coming 3-4 years of your skill level...
by that time ull be 21-22,more sensible and experienced, get a 1000cc
rather go up slow and enjoy every category than do something stupid on the best one and regret rest of the time...
lol quite a huge reply but these were the exact things goin on in my head before i bought my 600... ne other questions jus ask!