Hello George, I think it really comes down to whether or not you will sail single hand or with a partner. Cat and I have an early model M17 with the cast iron centerboard and we are pretty comfortable with our gear for several days but it would be difficult to setup the mast by myself unless I had a fixture on the trailer to help raise the mast. The M17 is about twice the displacement of the M15 and so a better boat for rough water. The head location isn't a problem and there is more room between the V-berth and the companionway, however the only place I can sit upright is the starboard quarterberth [I'm 5-9]. Both of these boats are really solid so if you buy an older one it may require some work but will be worth it. You can't go wrong with a Montgomery and besides, the lap strake hull looks so much better than a single chine hull- we always get compliments on our boat. Ron and Cathryn Goodspeed 1974 M17 #025 "hula pie"