Just wait for another couple of weeks and get a "no-ban" 20" Bushie. The Target model has a Heavy Barrel that weighs 3.5 lbs in itself...point being, a 20" Hbar is a heavy gun. Unless you plan to mostly conduct bench type shooting the Gov profile 20" would be a better way for you to go IMHO. However IIRC, Bushie does not sell the Gov profile barrel in complete rifles to civies but I am willing to bet that will change post Sept 14. But to answer your question, an A2 FH will come on the "no-ban" Bushies and on a 20" rig it is adequate. But if you are looking for the best you really have two choices, the Vortex or the Phantom. The Vortex is the absolute best in flash reduction but the design itself can be viewed as its main con. It has an open prong design that can get caught in shrubs if you plan to do some bush stalking. Second, there are storeis of the prings opening up after high round counts. THe Phantom on the other hand would be most probably be the best choice, specifically the 5C2. It is only slightly inferior to the Vortex's FH capabilites but it is more rugged and the model named above has a closed bottum, thereby acting as a compensater as well. Plus the closed bottum also reduces the dust signiture when firing from the prone.
Just my $.02