I have a 7D MKII ordered and decided I need another lens to go with it. The only short range lens I have is a 50 1.4 so I am wanting a zoom. I have several on my list but thinking I would like to have a 2.8. Don't want to pay the money for the Canon 17-55 IS so my other choices are the Canon 24-105 IS, Canon 18-135 stm but I think I would be giving up IQ. Also thinking the 15-85 IS anyone have any ideas which way to go?