No experience with the Stratus, but going with REI's rep for quality gear, would expect it is every bit as good as the BA.  I believe it's a new piece - haven't see it prior to your post.  Two differences I could see - $15 cheaper for the 'standard' pad and the larger outer tubes to hopefully keep you from rolling off.  Of course, if you have a BA bag and it's pad sleeve, that's no concern. 

Have you seen the new BA Insulated Q core?  It's 3.5 inches thick.  Costs a bit more, but an added inch of comfy goodness!  I may have to trade in my current BA!

pd