Just finished test firing the Thompson and it's pretty good. Fires at about 280 FPS with .20g BBs and has a really fast RPM. It's not as accurate as my M14 or M16, but of course that's due to the shorter barrel.
My main gripe with the weapon however is the battery compartment door. My 8.4V battery fits inside it alright, but the door is too big and it won't allow me to push the door in all the way and close the flap. The battery that Tokyo Marui reccomends for the gun doesn't fit properly into the stock!
Kit'age my lad, to make that tommy really shine, you'll want kits.
First off, the imitation wood, its made from a composite plastic, its a brittle material, any crack in it and it will start to crumble, and theres nothing you can do about it.
So you get a real wood kit, looks better, its stronger, and its a material you can work with! can't fit the battery you want? get a file and make room!
Second off, the body itself, its ABS plastic, its a strong mold secure plastic, it wont just break, beeing flexible in nature, but, after skirmishing a bit with it, you'll find that it scratches somewhat easilly, so when your tommy is looking scratched and ugly, get a metal body for it! it'll look nicer, even if it does get scratched again, and it'll last you longer.
Kits are the airsofters freind.
And when the box finally dies, thats a great time to tune it, its a short barreled Marui, so you'll want steel gears, steel ball bearings, a ventilated piston housing, and a good spring and piston, then she'll shoot brilliantly.