Can't help with the where to find one part, haven't kept an eye on them.
The couple of "down sides" I can think of;
Mags are expensive at $30-35 a piece, but they are well made, and you shouldn't really need more then two.
You need to remove a screw to take the slide off.
Early models had a diecast barrel bushing, they are known to fail, but they did fix it with a steel piece and will replace it if you happen to get one with the lower quality part.
Other then that they a well made and are the same size as real 1911.
I got mine late last summer and ran about 500 rounds through it without any problems, a couple others I know got them too (shooting their's made me buy mine) and haven't had any problems, one guy used his hard for a while without any issues.
So I'd say yes buy one