Once you get past the sizing issue (size listed on Amazon product page are not the correct sizes!), the protector is pretty good. I needed an XS for a small day-pack, and the price was great, clocking in at $16 with free Prime shipping. The protector is excellent for this price range. It's completely water proof and has a cinch that allows you to adjust size. The cinch cord is really high quality too, and feels like it won't wear away very easily over time from tightening/loosening it again and again. The material of the cover itself seems less apt for resistance to repeated insult. I have a feeling it may be the first thing to go on this product... but as it goes with everything, you should expect to get what you pay for. In this case, I am expecting a few good months of usage before I need to replace it; right on par with it's extremely affordable price point.

The only thing I don't really like about the pack (and this is really being finicky) is the bright yellow emblem on the outside of the cover. It blares vividly when I'm out in the wilderness, and I much prefer subtler tones when I'm out in the wild, but for $16 (compared to $40 at my local REI), it's hard to complain.

I very much recommend this rain cover, BUT MAKE SURE YOU DOUBLE CHECK THE TRUE SIZES! I had to return my first cover, because the sizing was incorrect!