You can run CM10/10.1 off the SD card. I'm doing it on my HD+ (
method 1,
method 2)and it can be done
on the HD as well, so you could avoid the rooting/update cat-and-mouse game if you wanted. However, development for those tablets doesn't seem to be as robust as for the original Color and Tablet. In fact, it's looking like it's stalled almost completely for the HD+.