I used a 3200 at the range the other day when it was raining and no they are not fog proof on the outside.I could still see the target at 100 yards without wiping the lens but it certainly was not clear.I have used the 3000,3200 and 4000 and 4200 and have owned a 3000 and 4000 and I find them to be the best value for their price ranges.To me the 3200 and 4200 are brighter than the leupold varixii and varixiii respectfully but their eye relief is a little shorter which has not been a problen for me or others that I know when mounted on 7mmremmags and 338win mags.The 4200 is to me a bit brighter than the 3200 but the difference is not great.