I try not to use my bags that have new vachetta on them, but my papillon and speedy have a great patina now so I dont mind normal rain, not pouring like crazy and stuff, and on the pouring like crazy/snow days I use my damier speedy!
I treat all my leather with applegard conditioner and waterproofing and have no problems in rain or snow - of course, I don't let the leather get soaked but it keeps it rain or snow safe for short exposures.
I wear LVs in all types of weather; doesn't matter to me. And vachetta dries and clears right back up (at least in my experience).