Dual band will work fine.
The Newegg review system is shot. People will either post scathing reviews when the problem actually exists between keyboard and chair, or they will give a good reason why not to buy and give a 5-egg rating.
Any brand will work, but stay away from the Airlink 101 and the non-business-class Buffalo products. Linksys (aka Cisco) has some good adapters, as does Asus. Netgear takes up the middle ground quality wise.
I can tell you what brand NOT to buy, but not what adapter to buy. I just don't have the experience there.