The foam weather strip won't standup over time thats why I desided on rubber. As to the cap one rv'er did put on the cap "PairaDocs" an he said it didn't work for him, an he thought it maybe was reducing his gas mileage.
DriVer on a post about unanswered questions for rv's, said WH didn't have a problem with it. I have not used it, don't see it as improving on the weather strip, told Newmar when I talked to them. Like you say will be glad when the snow's gone, next couple of days rain an in the 40's, but than colder, DARN
---"007"