I think, JW are not the only way to God. I know people from other christian groups, which have a much deeper and closer relationship to god and Jesus than the average witness. They also show that love to God trough the clean lifestyle, which they really practice (from there heard, not because it's a law).
Will they be destroid by God? When Jesus said, some will say... lord, lord, didn't we do this and that in your name?? Whom did he mean?
In my opinion, he mean the one, which did work for God to look good to other people but not from real love to God! Does anybody here really believe, that God or Jesus will tell them at the court:
You really loved us, helped other people by any chance and spent almost your whole time for us, but unfortunately you misunderstood that and this teaching...
But to the witness they would say:
You didn't have a close personal relationship to us and we didn't see you showing love, but, important is, that you got the right sense out of the bible. So you will be saved!
For my case, I'm still a witness. After some talks with elders, I'm not allowed to discuss my doubs with others in the meetings. Thats wy I enjoy this forum so much....