Welcome to the forum Russ. What I can say about your question of 38-42 foot is that you maybe able to get in more State parks with a 38 foot than a larger one.
Good luck, take your time and make sure it has what you want.
Mike & Donna with two rescues Rebel and Dixie, near Memphis, TN
2005 Itasca Horizon 40AD, 400 hp Cummins
2003 HD Electra Glide, 2007 Ford F-150 toad