If it were me, I'd get the 70-200mm f/2.8. Oh wait, it was me and I did! I'd been wanting the 135mm f/2L as well, but now that I have the 70-200mm f/2.8L IS II, not so much. It's still on the list, but way lower down. I got used to the weight pretty quickly (and with the help of a BlackRapid strap). 200mm is long enough for candids without causing a stir...or you can flaunt that big white lens, and people will move out of your way.