The router cited only supports b/g. For this reason, the adapter purchase should be based on affordability and aggregate recommendations (to assess quality).
(ie, I haven't seen a broad comparison of several different models of each type -- client hardware is not something sites like smallnetbuilder.com seem to spend any time reviewing)
Intel is still the gold standard. I believe that the market is in the early stages of the transition from high-end adapters to bridge-like devices such as this one
detachable antennas with standard (BNC) connectors -- this enables you to use cheap coax to position the antennas for best reception without regard to the placement of the computer
BNC was thinnet; most detachable antennas today use RP-SMA. You may have been referring to RP-TNC, which Linksys favored until 2005 or so. The use of coax pigtails causes attenuation, which may be considerable given the type cable used at that length. If positioning is an issue, you are better off with USB.
#182 TT: 13/DNVT, Precedence: Flash Override. Switch: Node Center. MSE forever.