Masochistically, I shall reply to this one.
First of all, kudos to you on your first build that works. Many of us weren't that fortunate and probably have a few broken parts to show for our "experience". I am one of them.
As far as the whole flash suppressor/muzzlebrake thing...here's the deal:
If it is DESIGNED as a COMPENSATOR, i.e., to vent gases from the barrel in such a manner as to compenate for recoil or muzzle flip, and is permanently attached, it can be considered post-ban legal.
There are several manufacturers out there (CavArms is one) that makes a muzzle brake that looks very much like a flash suppressor, but isn't.
The other option is a "faux-flash suppressor", one that LOOKS like a flash suppressor, but doesn't have the cuts all the way through and does not suppress flash in any way...just looks cool.
If you're doing the work yourself and are not fully familiar with the function of a muzzle brake, I recommend going "faux-flash suppressor" over making something that MIGHT be interpreted by the BATFE as a flash-suppressor.
Keep in mind that the BATFE has the final word on the difference.
The basic functional difference is while a flash suppressor's main purpose is to suppress the flash of the unburned powder out of the barrel, the muzzle brake (compensator) actually cuts recoil by venting gases in beneficial directions, like up and back.
All I know past that is that threaded/removable bad, permanently-attached, good.
Don't know squat about attaching a compensator with set screws. Sounds good, but I'm not the BATFE.
Panz
[bounce]