Just my opinion...
The OP requested an open question on what internals you guys would recommend...so listing off a bunch of stuff isn't out of line, especially when the OP didn't list what he's starting off with...
Whether or not he'd be allowed to use it is a moot point...there's plenty of games across Canada that would allow hot (i.e. over 400fps w/ 0.20g bbs) AEGs. Perhaps not many (if any) of the public games...but they're out there.
To the OP....can I have your M170 spring when you're done busting mechboxes...I've got a project build I'd like to try it out in!
Tys