I've seen the Montbell system, but I've heard of delamination problems with the pad.

I think velcro might be the ticket. Just how to attach it to the thinlite. What type of glue would work best to attach velcro to foam?

If I was using thicker foam I would cut an insert slit in the end to get greater surface area on the velcro. But with the 1/4" I'm using, that really isn't an option.