I have the 5T plates... so far so good. I think 5mm was a bit of an overkill, 4mm would probably have been about right.
I just used heavy duty velcro (
http://www.radioshack.com/product/in...uctId=2103345# I believe thats it... ) to mount the ESC to the standard Flux ESC mount; but I also don't use the post that ties the mount to the motor plate.