my Boomer almost always has on his collar and he has been mirochipped, however the only reason I make him wear the dreaded (to him) thing is because it is in the rulebook where I live. Though technically I'm not supposed to have him at all, I'm at least following the rules regarding: must be "fixed" must have front claw tendons snipped, must be microchipped, and must wear ID collar at all times. As far as I know he hated it at first, but eventually just got used to his new collar. Now I go and buy them according to season, though this year I already have his Christmas collar on him Bathtime is the only time that he regularly gets his collar removed and I find that when it is time to put it back on him, it helps if I play with him with it for a little while first and then leave him with it for 15 minutes or whatever and THEN come back and snap it on. He just doesn't seem to mind as much