Cherio, what do you plan to mow? Grass? Light brush? Tree trimmings (slash)? I've used three mowers on four different machines and can offer some experience, depending on the task at hand.The first thing to consider, of course, is not to get something that exceeds the aux hydraulics flow, and I would not want one that was wider than the machine, just so it wouldn't be a limiting factor on where you can go with it.
Everything Attachments makes a dedicated line for skidsteers, as well as their main fare for tractors.