I got alucard from an anime series called hellsing. I dont particularly care for anime, but the characters name was alucard, it is Dracula spelled backwards.

SWR, has recently changed hands. Joe Gadini was the owner. And He has the BEST record for warrenty on his products. He upgraded my .45 can for free to a new version (most other companies charge half the price of a new one to upgrade or repair, some more, some less then that) He would literally repair your can if you ran it over with a D4 caterpiller.
I'm sure that the new owners Matt Pallet will keep the same warrenty going.
See this post about SWR:
http://www.silencertests.com/forum/viewtopic.php?t=6930

The only draw bak I can think about for quick detach cans is you have to get the correct flash hider. The gemtech halo will mount on any AR-15 with a standard flash hider and a peel washer (if any of this is incorrect, please correct me) Witch is nice cause if you have a bunch of AR-15, you can just move the can around.
The AAC needs to have a special flash hider installed, which is $85. Unless you dont mind screwing it off to put it on another gun, you will have to buy a flash hider for each gun.

But the mounting systems on quick detaches are great, no draw backs as compared to regular threaded.