Samoset, I used the Integral Designs South Col as a throw down thru-hiking the AT several years ago, and was very pleased, though twice, when I was totally unprotected in an hours-long driving rain, I slept in a puddle. Never figured out how the water got in, but did not seem to be through the cloth itself or the sealed seams. I carried a poncho, but rarely used it for shelter, and in the two rains mentioned above,I had used it to wrap my pack. There was a bit of a learning curve, knowing how much to open to avoid condensation, but had very little trouble.

More recently, I have bee using one of Ron Bell's designs, and I love it. Bell is Mountain Laurel Designs and I think a super designer. I have a poncho/tarp and pack in addition to the bivy,and I'm delighted with them. I probably have at least a hundred nights in the bivy, though I have never tried it in the open in the kind of rain that breached the South Col. Always set up my tarp like a good boy when there seemed to be a chance of rain.

I'm convinced that you can't go very far wrong with either company, but at the moment, I think I would recommend One of Ron Bell's designs.

best, jcp