For what it's worth I have never had my faith challenged by a JW. They have knocked on my door, offered me a copy of their magazine, The Tower i think, and pointed out to me the names and phone numbers that I can contact if I'd like to discuss issues of faith. That's pretty much it... probably because I had a crying baby and I said I was busy

I assume that there must be more fervent members of JW out there but I guess if every faith was judged by their most fervent then nearly all faith sytems could be held up for criticism in terms of pushiness.