I just read a post someplace and it talked about swapping a CTR head onto a GSR. I'm getting a GSR soon and i've already made some decisions on which way to go. Could anybody tell my why this swap (CTR head on a GSR) would be a good idea. i havent' heard a lot about it. I also read that swapping in CTR heads would be a good move. Some opinon and advice would be appreciated. Thanks!!