Canon 7D user thinking of switching to Nikon D600, big mistake?

Changing camera systems when you're short on cash, which you mention, isn't a great idea.

You've already soaked up the depreciation on the gear ... so by definition you're taking a financial hit. I suggest using what you've got until it wears out or until you've got the cash so that finances aren't an issue. (That Nikon will be cheaper later on anyway.)

And changing bodies isn't going to in and of itself, cause something magical to happen in your photos.

In normal ISOs the Canon 7 does a fine job ... I have one. The handling of the 7 is particularly fine ... I like it better than the Canon 6 even.

The lastest Nikons may be a step ahead in sensor tech ... which matters only if you're shooting in the dark and making some coin with your photos.

I work with a variety of photographers on jobs ... and I get photos from Canon 40s, XTIs, even a Canon 10 and Nikon 300s etc. The camera model generally makes no difference whatsoever ... except in a few cases when we really want to push the size of the pic.

The Canon lens is both good and versatile. (I have the Tokina 16-50 instead, which was a good bit less expensive when I bought it. Now, the Tokina is discontinued so for the same cost, I'd get the Canon in a heartbeat.)