My personal bike is a bit old to do any comparison (1988 rm 250), but I do a lot of research and have been looking to upgrade myself. Below is what I have found to be a general consensus on the RMs in that time period (purely based on reading, not riding) Pretty good cosensus that the RMs are one of the better bikes on the low and mid range and they always seem to bode well on the handling side of things. The RMs have also always been known for having a good smooth shifting tranny, however I have heard that the clutch components like the basket and plates can be a bit fragile. Really can't say I've gotten a read on the suspension for the bikes of that time though. I know that as far as two strokes go, the new RMs are at the top of the heap from a magazine "shoot out" point of view. Don't know if any of this "theoretical" bantering helps you, but it reflects the research that I've done to this point. I have not seen or read anything that would discourage me from a 99 RM 250 at the right price, but I'm also just a novice so take it with a grain of salt. Good luck!!
Trev