PTO HP and 3-point hitch lift limits are points to consider but you also have to factor in the mower extension when it is off the ground.
I was thinking of going with the Del Morino Flipper Super 186 and I was within these specs but was advised by people smarter than me that it was too heavy for my tractor with the mower extended out, especially when being in the vertical position.
And I ended up saving me quite a bit by going with the advice of others - both in the cost of the mower and a potential broken tractor.
Don't have mine yet, but it arrived at the dealership today and I will be getting it next week!