Motorola Q

I currently use BT tethering (just because I dont want to muck around with my iBooks kernal files). My only complaint I guess is that, after some inactivity (like typing this post after the page is loaded), the connection drops. It doesn't drop if I am surfing or constantly sending or receiveing.

Has anyone successfully made a USB dun connection without really risking thier Mac at all? If you risked the files, is it really worth it? Does it stay connected even after no activity?

thanx guys
j