Thanks Ed. Yes, my buddy is really enjoying them.
1) No, I cheaped out and used the primer and clear I had on hand. What I used was:
Speedokote SMR-210 Grey 2K Primer w/ SMR-211 activator
Speedokote SMR-1150 Urethane Clear w/ SMR-1102-Q Activator Medium.
Fortunately, I had no compatibility issues.
2) Nope, I sprayed the BIN straight from the (fresh) can. It doesn't require any thinning when spraying with a 1.4mm tip. If you have a can that's been open for a while you might want to add a little denatured alcohol.
3) Unfortunately, no. Life is getting in the way, and I decided I'm not going to paint my X-MTMs until I finish building the matching center and rear channels, and subwoofers. Hopefully later this fall. Still leaning towards metal flake though...