I'd suspect the people writing reviews that their AP didn't work with 360 don't set it up properly first. You have to setup the AP on a PC before you can plug the 360 into it.
I have 2 wireless APs. Both Netgear WNHDE111. They are 5ghz wireless N. They allow two ethernet connections, so I have my PS3 and 360 connected to one AP. I've read reviews that they would drop connections every now and again, sure enough they do drop connections. I have to reset the one I use for my PC sometimes frequently, something like 3-4 times in a row. The one my game machines are on doesn't need that done. But I'm not playing them every day like I use my PC daily.
XBL Gamertag- Yrd
PSN - Yerd
Steam - Yrd