Yeah, the default card in my X220 was a piece of crap. I got one of these for $15 and replaced it myself (took 10 minutes) and it's been muuuuch better.
http://www.ebay.com/itm/Intel-Advanced-N-6205-wifi-card-Thin...
(I remember this was actually a customization option when I bought it and I stupidly didn't pick it. So you don't have to get a macbook, just read carefully when you get another thinkpad.)