This morning my breathable rain jacket stopped being waterproof. Rather than beading and running off, the water just soaked right through. The jacket has only been lightly used and isn't visibly worn so I'd rather not buy a new one yet. Does anybody have any experience with waterproofing sprays (i.e. Grangers, Nikwax, etc)? If so, which one did you use and how well did it work? Did you have to constantly reapply it? Did it affect the breathability of the jacket?