they do the same exact job actually.. and the rotozip is much more accurate and doesnt' waste as much wood, so you can take a 12 inch woofer cut out, and make an 8 inch ring, 10 inch ring and component ring, with a tweeter ring, where as the router would just chew all that wood up.
I can get that skil for 60 locally and I'm thinking about it.... but I was looking around for deals //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif... the rotozip is interesting and it would be nice to have both but I think I'd rather have the router if it was one or the other....