The XXL's are about to be re-released by Robot Power very soon, send them an email chris at robotpower.com and he should be able to tell you more.

This is what he told me when I ordered the XL last month

We are introducing a new Scorpion XXL in the next couple of weeks. Don't know if you are interested or not. This is a 30A per channel dual controller vice the 12A for the XL. It has many improved features over the XL