I think that I would go with 70-200 f4 IS if I were you. It is a fantastic lens, focuses extremely fast, is sharp wide open, and has a 4 stop IS...hard to beat combination. Here is a sunset just taken with 5D Mark ll and said lens( iso 200, 70mm, 5.6 at 1/125).[img]/cfs-file.ashx/__key/CommunityServer.Components.UserFiles/00.00.00.22.00/Aptos-Sunset_2D00_0449-_5B00_800x600_5D00_.jpg[/img]