My 7D has served me very well for the past 3 years, paired with a nice better-than-kit lens (Tamron 17-50mm F2.8). But I just got the 5D3 and now I have a bit of dilemma.
I bought the 5D3 for portraits and significant improvements in low light sports - and I already have the lenses for this purpose (50mm f1.4, 85mm f1.8, 70-200mm f2.8L)
These account for about 95% of all pictures I have taken with the 7D. The other 5% I guess are general landscape, walk-around pics where the Tamron did just fine.
But the Tamron won't work on a full frame body, and I'm not sure about spending around an $1000 on an acceptable full frame kit lens, just for 5% of my photography. Although I do have a very capable P&S for general purpose shooting now - the Sony RX100.
So my dilemma is to sell the 7D + tamron kit (for around $1400), and be without a general purpose lens range for the 5D3, or just keep everything. If I do keep the 7D+tamron, is it worth keeping for just 5% of the time when I might use it?
I know this is ultimately a decision I have to make myself. But I hope I will hear some stories from other 7D --> 5DIII upgraders and see if I can get some more insight in general.