I replaced this unit because its predecessor broke down after four years, and three repairmen could not diagnose the problem - I bought and returned various parts to no avail. The new model is almost identical but with enough of a difference to make the replacement installation a real headache. The fan housing is larger, so the exhaust hole does not line up with the old duct - I needed to cut a new larger hole in the cabinet floor. This unit is not meant for granite countertops as far as I can tell. Two brackets on either side need to be secured (actually stabilized) under the counter top and drilling into granite that close to the opening for the unit does not seem wise, nor is it easy for the average do-it-yourselfer. I ended up stabilizing the unit with angle irons to the back of the cabinet (also not easy). The whole unit rests on metal legs that you have to attach to the unit prior to installation. But once put it in place, there is no way to adjust the height so that the unit is flush with the counter top (even the best pre-measurement will be off a bit). Moreover, the provided screws for the legs did not fit and I had supply my own. The new unit is about 1/4 inch wider than the old unit and this required shaving off 1/8 inch of granite on either side to accommodate it - again, not easy unless you happen to have a diamond tile saw. The old unit had a continuous sliding switch to control the power; the switch on the new unit has just four discrete levels and is somewhat difficult to manipulate. After three full days spent installing this thing, it works, but if the life of these is only four years then I would recommend a service plan (I bought the 5-year plan from Geek Squad for about a hundred bucks). My only reason to "recommend this to a friend" is that it is one of a few, if not the only, option for venting a range on a kitchen island. And, it does do a good job in that respect.