Hi Nathan,
I had a 250x from new (04) to ride timecard enduros and H&H's, and would still have it if some scrote hadn't stolen it in 2012.
Bought untried, and after a 450 Husaberg, it was somewhat underwhelming at first, but I soon found that I was quite a lot quicker on it for far longer than on the bigger bike.
After the valves settled in, and the spokes tighten up, it was as reliable as a housebrick! I opened the airbox slightly and re-jetted it, but left the original silencer on to keep it quiet. I fitted a full road kit (which I think they now have as standard) with glass headlight and brake light switches, a bash plate, and some bar risers and had the suspension set up. Flat out was around 67 mph, so as a rally bike it struggled (hence the 640
) but in any tight stuff it was outstanding. As a trail bike it is as good as any enduro, ie the seat is hard and road work is tedious, but as soon as you get off tarmac it excels.
As I said, I would still have mine today, and am confident it would still be a useful little bike. When I got the urge for a trail bike again, I gave in to the dark side though, and bought a two stroke.....
Anything else you want to know, give me a shout.
Cheers
Mark