If you go to the Thai Silks web site that Roger had mentioned, you will see a wide variety. Since I didn't know anything about silk, I wanted to K.I.S.S.
I chose the lightest and plainest one in the #21 group, maybe #21H. I think that is considerably lighter and thinner than what Roger was into. Maybe he knew something about silk and wanted something more long-term durable. Obviously you can get some fancy styles, but that isn't _me_.
When I started with the 4 yards, it was 3.56 ounces. By the time I had the liner crudely fashioned, it was 2.01 ounces. By the time I trimmed it down slightly, I ended up with 1.87 ounces.
If you are the kind of sleeper who thrashes around a lot, then I could understand the need for a heavier silk.
As for PJ styling, you could probably follow the example of Hugh Hefner. It works for him.
–B.G.–