Only for 'round town, or maybe car camping, which means, at 24 oz. for an XL, it's generally not worth it unless you got it for free (like me--as a gift). And there are better alternatives for 'round town.
The standard R2 is borderline for backcountry use, and so is the R2 bodyrug (no longer made?), as these are far bulkier than their down or synth. counterparts. I do like the Bodyrug in really cold weather when perspiration is an issue, as it dries quickly, vents easily, but is very warm. Hard to pack, though. The R1 is a classic...