Dont know about the USB adapter. I do have the same NetGear router though. Bought it a couple of months ago and it seems okay. Have seen it lose signal for a few seconds sometimes but I have seen worse from D-Link and Belkin. I'd still rate LinkSys higher but for the price this isn't a bad bet at all.
I use that one for both desktops and wireless laptops, it's been sturdy and I haven't had a single problem with it. Considering how bad the Comcast cable can get sometimes, this part is the easy thing to deal with. At least I don't need to reboot it as often as the cable modem.