Dreamsack: silk sheet for hostel sleep?

Who out there has used a DreamSack, or some similar sleepsheet, before? I need to know…

Travelers time and again have told us that one of the things they wished they'd left home was their sleeping bag. They didn’t camp enough to merit the carry, and they never needed it in hostels. As an alternative, many have just carried a sleep sheet, for use in hostels and such.
Round-the-World Traveler Michelle Moore, for example, was telling me about her DreamSack:

I got the sleep sack from either Magellan’s or Travel Smith about 5 years ago and I still use the same one. Its great. Either place calls them Dreamsacks and they sell for about $69.00 with Travel Smith and $59.00 with Magellan’s. Mine is silk so it will dry in no time! I use it everywhere I go and it rolls up pretty small…. They have the single size and a double. I use the single. Just be careful to wash it by itself because I got a burgundy one and the color still runs no matter how many times I wash it!

So I started checking out DreamSacks’ website.
Their flagship products are side- and top-opening silk sleep sheets. After wool, the site notes that silk is the warmest natural material; it also is lightweight, and packs down compactly. So I’m thinking pretty hard about getting a DreamSack.
Before I do though, I’m wondering if anyone else has used one, or if you use something similar. What do you use? What’s been your experience? I think I’ll kick an email over to Joe E at the Travel Gear Blog as well, and see if can serve me up a bit’o insight.