XRAY - Model racing cars

I have been racing for a couple of years and i'm going to upgrade from a schumacher sst to a Xray but not sure which one to go for.
I cannot really afford to get a FK05 - will probably be looking second hand but not sure which would be best.

I've been looking for a used factory kit - on the assumption thats its better to go for the best if possible.- am i right? or would a raycer or evo2 be better? I'l be running 27 stock on low grip carpet

Also , a dealer said the new FK05 is a lower spec than the FK ...is this true or just a sales pitch to try to shift the old ones despite a higher price?

sorry about so many questions
but advice would be appreciated
thanks
marc