(1) It can work very well, but it works best on things that were made for water repellant, and not so well on things that weren't. Try it on a pair of jeans, and you'll see what I mean. Colleen noticed the same thing.

(2) DON'T USE THE WASH IN TYPE. Get the kind that you spray on, and then put it back in the dryer. You have pretty good control over where you put the stuff that way. The wash in stuff is going to make the inside of your jacket water resistant, too, and then it won't breathe nearly as well.