These are $99 a pair and seem to perform better than the AutoSock and Multi-a-Grip. I'm also in the DC area and don't want to shell out $$ for winter tires and wheels when it only snows <5 times a year. I have xdrive and summer tires, and my car was useless during this past snow (less than 3 inches). I've been reading up on these 'snow socks' and these guys look the best so far.
If anyone knows otherwise, please speak up.
http://www.ecstuning.com/ES2129939/