Basically, I echo everything that "dave h" said. I'm sitting here at work with wet sleeves on my cotton shirt because I wore this jacket beneath my motorcycle armor. The armor's made of mesh Goretex, so I needed something to stop the light rain this morning. This Columbia jacket did not do the job. Leaked in the upper sleeves (because of leaky seams) and upper chest (through the zipper).

I also echo Dave's pluses - it packs down very small, and it's very effective as an outer layer to block wind, on cold days on the bike. But it is NOT a rain jacket.