Something else to think about is what a hassle it is to change the throttle or idle cables should they break. that is my lazy man argument for the day. It sure does look clean though!
I saw a pic where a guy drilled a few inches away from his master cylinder and ran the line through there. I thought that looked better than having it out.
I hope it will work out. You will be the first with a 1,25" ape. Personally the throttle and idle was for me more a problem, that why I went for the internal throttle.