In reply to iamaclimber:
Have had no experience with the Pro Lite but I use a Small version of the XTherm.
Very happy with it. I upgraded from an older version of the Xlite.
Yes, it has more crisp packets in it to reflect the heat and is crinkly but not enough to disturb me sleeping.
You have to blow it up whereas the Pro Lite is self-inflating (although you always end up blowing into it anyway)
XTherm is lighter in weight due to above
XTherm is warmer R value of 5.7 vs 3.8
Have used mine alot and trashed it about a bit and is still perfectly in tact.
XTherm is smaller.
On paper, I'd say the Xtherm is superior. I wouldn't want to be using it at altitude and blowing it up. However, you do get special dry bags that work as pumps (you can also easily use a plastic bag).