The thing i have heard about KTMs is the availibility of parts. Some advice is when you purchase the bikes, also purchase a new top end kit and some other items that need to be replaced. This is heresay, but it may just depend on the dealer. If you choose an SX85 you will have to adapt to it because it is definitly different than your RT100. I have heard many great things about the KTMs and with the new suspension this year i'm sure you'll be satisfied with whatver you get. You should consider the new SX105 also. It will last you longer than the 85 will. Well at least you wont outgrow it that quick.