Just wanted to put this up for anyone searching for where to have valve / seat work done, I just got my head back from MXTime (www.mxtime.com) and it looks fantastic. Dave removed my old valves / springs and replaced them with new Faction components. Prices extremely reasonable, and time from when it left my door to when it got back was 1 week exactly. Big thumbs up to Dave... thanks very much! PS - I was a little nervous about pulling the head / doing the piston due to all the talk about 4-strokes being hard to work on (I've done one other piston replacement and that was on a 2t). I can't speak for the other brands, but in the case of the CRF its just not true. If you've replaced a shim, you're pretty much all the way to having the head off, and once you've got the head off, its just a couple more bolts to get the cylinder out and there you go. Other than being careful for the cam chain I'd say its about the same, difficulty wise. The hardest part of the whole thing is trying not to shoot your eye out with the piston wristpin clips (or lose them into the case). I found that swearing loudly helps FYI.