need some honest(non fanboy) advice.

[RTfuture]

So I've finnaly got the funds saved to upgrade my camera body. I've had a 60d for the last 4 years, and excited to make the step up.
I have £2,000(UK) Which is just enough to buy a 5D MKiii. OR a 7d MKii with £500 to spare... Which I would put back in to go towards some glass etc etc.

I've looked at endless comparisons, and still feel no closer to a decision. In terms of what I need in a camera.
The money I make from photography is very low light work. I shoot at ISO 2500 regularly, and can't push the 60d any further. So good low light performance is a must.
However, I'm starting to do more portrait work also, and have one eye on the future.
From what I've seen, the 7d looks like i'd get more for my money. But not sure if I want another APS-C. Does this REALLY matter though?! Please... Any further clarity will help!

Thank you.

www.remember the future.co.uk

[RexGig]

Congratulations! Your 5D III should serve you well. A "pro" camera body is, indeed, a step upward into another class of camera. A 7D Mark II would have been a very good choice, too. This is a wonderful time to be a photographer. 

I very nearly bought a 5D Mark III, myself, with the most recent price drop, but decided a second 7D Mark II would be the better choice, in my particular circumstances. (APS-C is the norm for evidentiary/forensic images, and during personal time, I love birds; it is Spring Migration now! Plus, I can use a Nikon D700 for my "full-frame" needs.) The money I saved by buying the 7D II can go toward a nice lens, or another 600EX-RT Speedlite.