Silnylon poncho, single wall tent, backpack. All three wetted out and allowed water where water should never be. So silnylon is off my list. Just because something is ultra light does not make it on the trail with me if it fails at it's purpose and has to be backed up with extra water proofing material. The backpack was lined with heavy plastic bag or pack cover, and single wall tent needed an extra cover.

As a result I carry a slightly heavier polyurethane poncho (waterproof in heavy downpours) and is also my backcover, groundcloth, picnic blanket in the sunshine, sit-upon over wet log, well you just can't get silnylon to be tough in rough and tough conditions.