Try out both mowers before you buy one and see which you like better. Dealers around here have arranged that for me in the past.
What are these "maintenance issues" I keep hearing about? I've been using walkers as my primary mowers since 1988. Only had 2 events where it broke in the field. Good news is the interlocks only work in forward so in a pinch you can drive them backwards into the trailer using the starter.
I have ford cm222. With that machine you feet are on a platform and don't move. I prefer the little movements in having my feet on the deck. My legs never get stiff or restless.
Walkers are great for fall clean ups. I blow all the leaves onto the lawn, raise only the front of the deck and vacuum them up. It also gives me a chance to sit down for awhile. You can suck the leaves off pavement too, it just takes 2 or 3 passes to get the shredded bits picked up.