There have been a lot of good choices for both of the units. I have camped in a MH and also a 5er. I guess it is going to be whatever suits the 2 of you the best. I chose a 5er as when you have it set up you have a vehicle that you can use to sight-see and be a grocery getter without having two complete drive trains to keep serviced as you would with a toad. As some said you can't very easy back up a MH pulling a toad. I do feel that if both are the same overall length unless the MH has the same amount of slides as a 5er then the 5er "seems" to have more room as you do not lose any for the cockpit area.
Whatever you choose, Enjoy Retirement and your RV. Happy Camping and Good Luck.