Ok, I got my swatch, and did some more reading.

The literature over on backpacking lite seems to indicate that this stuff won't work well... if I'm comparing apples to apples over the course of several years.

However, I filled a jar, covered the top with the 4x4 inch piece of fabric, and I'm not really getting soak through. I mean, the sticker that sail-rite put on the middle of the swatch is slightly damp, but that's it - after over an hour. The volume inside the jar hasn't changed either (at least, not within my means of measuring it.

Anybody have another suggested means of testing waterproofness??

Steadman