I have both pads, the torsolite and the prolite 3 short. The torsolite is a little bit more comfortable and warm than the prolite 3, except of course that it is smaller. It does not work very well for me by itself, so I use it in combination with a Gossamer Gear torso sized nitelite pad.
The combination of the two pads gives a total length of 60 inches compared to 48 for the thermarest. I find that combination way more comfortable at the same weight (10 oz + 3.25 oz) as the thermarest.
If you use a backpack made to take a pad as a frame, like the Gossamer gear packs, or similar, the above combination works really well.