I'm not going to tell you anything that hasn't been said. I had a FT Sentinel, and stripped the threads within about 2 weeks, just by carrying it around in a loose pocket. Twas a good mod though up to that point.
Aluminium is absolutely fine, if worked well, and if not, as others have stated, be careful with the threads. Hey, the beastmaster is aluminium, aloooomin-um even. No, don't thank me, America.