There's always been the tug of war between getting a full metal pistol vs. getting a "better" pistol and "having" to upgrade it to metal.
Common arguments...all of which are true:
- metal kits are expensive
- the lemon/fail rate of a TM pistol is very, very low
- Plastic pistols might run for a long, long time without any issue on duster (which they're designed for)...and maybe on propane (which is pushing them beyond their original spec).
- metal feels good
- "upgrading" stock pistols is one of the fastest ways to ruin a perfectly good pistol
- cheap full metal pistols might work (i.e. the shoot a bb out when you pull the trigger) but they probably don't have the fine points/finishes done nicely
If you want a cheap full metal pistol and really just intend on using it occasionally or not at all...get whatever you want. If you want a gaming pistol...then go for reliability and performance. If you don't end up using it as much as you thought...then you've "over-spent" regardless of what you've bought.
"Compatibility" in gas blow backs is greatly abused. You might luck out and everything is drop in....you might blow $100 and the part may not work for no obvious reason. All you're doing by going the TM route is hedging your bets.
Personally I'd buy a TM 1911/MEU and upgrade to a frame/slide kit...which is mega bucks and why I haven't done it yet.
Best of luck,