Wheelhorse lawn mowers, depending on the brand, can be very reliable. However, if one wants real power and a piece of equipment that will survive your best of needs, it is always best to go with a John Deere instead.
The Toro Wheel Horse garden tractor is pretty good. It is sturdy and easy to use. It does an adequate job on grass, but could be better. Some problems have been reported with the carburetor which sometimes needs draining in order to run. The ignition switch is also not as sturdy as some would like.
Of course! I've had a Wheelhorse for about 10 years now and it's served me well. It's certainly not right for everybody and every situation but it's pretty good for what it is. I recommend getting a good warranty with it. It's not that it's necessarily going to break but it's always better to be safe than sorry!