Can't help you on the claim side, but don't notify your current insurance co. if you just move the RV to another company. You will lose your multi-vehicle discount, if any. And if you have other policies in force, like PLUP's, they will jack your coverage on that as well.
What I like is your current insurance co. has less overall liability exposure, when you move the RV to a separate company (rate wise at least), and they therefore "punish" you for not keeping all the vehicles under one policy.
Don't tell them anything that your not required by your state laws. I was nice and told them what they asked for and was punished for it.