Have you ever had a camera fail and actually needed your backup? I don't particularly mean through catastrophe (Fall, Water damage etc.) but has your camera just failed to work and you had to revert to your backup. I'm considering selling my backup to fund one of the two lenses I'm after. I have a very low shutter count 5D3 and a 1D3 as my backup and the 2 lenses in my want list right now are a 35 f2 IS and a 300F4. I realize for professionals a backup is sort of a must have. I kind of have a paid gig, I trade tuition at my Jiu-Jitsu school for photographing events, seminars, and some classes.