Deciding can be an emotional merry go round. We just purchased a 2007 Montana 3400RL because my wife insisted on the rear living room. She said it felt like home. What husband can argue with that logic?
Yes, the slides block most of the unit when retracted but as long as you can get to the bathroom on those long trips, for us it doesn't matter. With ours, the bathroom is located in the bedroom and is located prior to the area with the slides so it is always accessible. My only complaint is that in our Montana, the bathroom and shower are in different locations and if you have company, they have to come into the bedroom to use the toilet. I have seen newer models that combine both toilet and shower and have a door that allows closing off the bathroom from the bedroom for more privacy. That may be something you want to consider in your search. Good luck. Take your time as you most likely will live with your choice for a long time. I like the fifth wheels because of the extra space, storage capabilities, and overall feeling of stability, both parked and on the road.