Ok, I am a travel nut in our camper and that thing doesn't go out of the driveway without my sewing machine and plenty of projects. We stay in it for months at a time and there are many days I quilt all day long. About your mid arm, you have to protect it the best way you can, locking it down and keeping it clean. Leaving it exposed in the back of the toy hauler would not be a choice for me, it will get knocked about a great deal. If you can take it apart easily enough and store it while driving, then do it. We have been pulling a camper now for over 23 years now and I have stories I can tell you about the things that fell or came loose while traveling, we never know what to expect when we open the doors. Good luck.