I know these have been discussed here before, but I still can't make the decision. http://www.katzeyeoptics.com/cat--Canon-DSLRs--cat_canon.html I manual focus alot with my 30D and have been considering getting the Katzeye split-screen with cross hairs and brightener (total a bit more than $200). I'm nervous about putting it in myself, but my camera shop's repair tech (who I trust) will do it for about $25. So ... thoughts? Is the screen worth it? Will I miss the cross hairs if I don't get them?