I've searched the archives, but I haven't found what I'm looking for.

I'm thinking about picking up a Rack Pack I from Sierra Trading Post. They're $77 and I found a 20% off coupon, too. Plus they have a very liberal return policy.

This model doesn't come with the rain cover. Any idea how it might hold up to commuting in the wet? My commute is about 30-35 minutes. I try to avoid downpours by waiting at work or home until it clears up a bit, but I'll bike in some moderate rain.

Thanks!