No, but I'd likely buy a high MP 1-series body.
You don't know as yet, but I know you will buy the 7D2, despite what you already stated.
Because it has an amazing autofocus.
Because GPS is a feature that will be very useful in many situations.
Because you'll admit to yourself that price is not the only
advantage of a crop body (well, you already admitted it when you recently modified your previous convinction by stating that it's the main
advantage, not that you were wrong before, but because the 7D2 didn't exist yet): apart from the other advantages, you might find that, with good light, your 600L
on its 20 MP sensor produces better images than 600L
+1,4x extender on FF without losing 1 f/stop and with the plus of slightly more reach.
Because having 1Dx+600 and 7D2+70-300 handy (or the opposite on occasion) can be really useful.
Because it's a nice toy to play with.
Because it's cheap, it costs only a small fraction of the value of all your gear put together.
Because the Black Rapid Double Strap is cool.
But, most of all, because I need your hands-on advice to help me decide: 70D or 7D2?