Ok, since a Phantom is open on all 4 sides and creates a dust signature...
How well does Kurt's elongated A2 Flash Hider hide muzzle flash compared to a Phantom/Vortex? They claim it is just like an A2 except longer, so I am guessing it has a closed bottom half right?
There's also this one (A3G2):
I don't think it looks as nice though, but I'll go with whichever one supresses flash best without creating a dust signature as long as the flash supression is as good as the Phantom/Vortex.
Edited for one additional question.
If a flash hider is only open at the top, thus venting out of the top, doesn't it also act (atleast a little) like a compensator, keeping the muzzle rise down a bit?
The KKF A3 hider is somewhere between the regular A2 hider and the Vortex/Phantom hiders in terms of flash suppression. It is identical to the A2 hider except for length, including having no slots on the bottom so there it wont kick up dust. I've heard people say that the A2 hiders have some compensation but I've never noticed it.