We've been using a Travasak for many years and love it. We started using it because we had a corner bed (hard to make). Now we even use it on our queen walk-around bed.
As 2gypsies noted, you have to like sleeping in a sleeping bag. But since there are sheets, it doesn't really feel like a regular sleeping bag to me. However, if you like nice tight sheets on your bed, this may not be for you. I don't know how the newer Superbags are, but in our Travasak, the sheet is plenty big, so can bunch up a little here and there. Doesn't really bother us though.
I like the fact that I can zip it up half-way or more and my spouse can't steal the blanket!
It took me a few tries to figure out a good system for putting the velcro sheets back into the sleeping bag after washing. Now it's a breeze.
2002 Itasca Suncruiser 32V
2012 Suzuki Grand Vitara