It seems that the 7D is getting no love... ;~;
Image quality won't be improved because they share the same sensor. Most of the things he shoots are stationary and don't require an advanced auto focus system or a higher frames per second rate.. so that's why.
I'm a fan of the 7d and getting it used for $700 is a steal, but it is all about the body that is right for the shooter.
700$, That is pretty cheap.
About 2 or three months ago, I bought a used 7D with less than 2500 actuations and a 28-135 for the bargain basement price of $650. I then turned around and sold the 7D for 700ish and the lens for 200ish... so I made an easy $250ish.
So... yeah... cheap.
Did you report this as capital gains? ...
All my money is in the cook islands... sons a bitches won't give it back though. :/