The problem with the older M&P's like that, is that changing out parts will become a little more difficult over time, as there are vast differences between a new Model 10 (think they are up to a 10-14 now?!) and that old five screw.
The best advice that I can give you, is obtain the newest model 10 you can find if you are truly going to build it into a race gun for reasons of practicality and servicing.
I would advise obtaining one with the frame mounted firing pin for the reason that it does have a much heavier frame. Will it last longer than a previous frame- I don't know, but it does give more weight. Another factor is, IIRC, the cylinders on these are marginally longer, which might be a consideration.
Another factor on the cylinder, is the fact that the newer ones there are no locating pins on the ejector to fall out and mess with the timing. The newer cylinders all have ejectors that are cut in a way to eliminate the pins. Also, the ejectors aren't fitted to each cylinder (but of course must be fitted to the gun by use of a cutting hand, or each ratchet filed individually). This way, if the ratchets get too worn, just order a new ejector and fit it to the gun- no mess or fuss. If you shoot enough, this will need to be done.
Probably need a longer hand first, though.
I'm certain I left a lot out, but that is it in a nutshell. I'd suggest looking through one of the places S&W dumps inventory to and find a deal on a new Model 10 of the most current design change.
