I have owned a few of the old Snapper pro walkbehinds and loved them. I have also owned Turf Tracers. The company I now work for has a 40" Grandstand and a couple of Exmark Metro's. I recently posted a thread about the speed of the Grandstand vs the Metro with a velke. This is my experience with a 40 GS.
1. Slow, the Metro with a velke will out mow the GS.
2. Heavy, Much heavier than a walkbehind and with the larger tires it is hard to turn without tearing up the turf.
3. Controls, controls are awkward compared to pistol grips or ECS. You have to move your hands off the stationary handles to reverse the machine. Basically you are not holding on to anything.
4. The 40 is not a machine for hills. It will not hold the hills that you can mow with a walkbehind.
5. The deck is HEAVY. to raise the deck you are raising the entire cutting system, including the engine. (on the 40, don't know about the 52).
This is just my opinion, I have run a lot of walk behinds over the years and I am not impressed at all with the 40" Grandstand. Toro does still make the floating deck, hydro walk behind with the pistol grips for around the same price as the Snapper. I have 0 experience with the new Snapper/Ferris WB