I've had one for about 10 years. Mine is the old square style where the new one is a more ergonomic one with rounded edges. I can't complain. It gives successful hatches. No telling how many birds it's hatched since I've had it. I do use it pretty well through the warm months constantly with only short breaks to clean out the plastic liner. My only gripe is I never have marked the proper water reservoir to fill and it's a pain to get the egg turner full of eggs out as they only supply you with 3 clips to keep them in, 3 racks don't have clips and it's frustrating to move attempting not to let the 3 racks fall out and break the eggs. Also the main structure of the turner feels very flimsy. It flexes when full of eggs when you pick it up, always worried it's going to break as well. I'd like to come up with a system to be able to see the water level with the top on then put a little aquarium tube in the right reservoir then squeeze a bottle to fill it up.
As far as temp control. No complaints there. It's preset and I never had to adjust. I hatch ducks, chickens and game birds in it. Everything hatches when it's supposed to. Hatch percentages are always very high. I have Dickey's and GQF cabinets and it's just as effective as them with reduced space of course. I depend on the styrofoam one for smaller clutches of eggs and put several different ones in at a time. For instance right now I have 12 dutch bantams, 11 call ducks and 60 jumbo coturnix in the turner then another 15-20 coturnix on the floor next to it. It's generally that way different species with different hatch dates and overfull but it hatches well every time. At least this time the quail and chickens will hatch on the same day. I don't do anything special for a hatch in it. The humidity level is not raised for a hatch. The vent plug is not pulled for the hatch either. When they dry I put them in the brooder so the top is opened 2 or 3 times during the hatch to remove them and it doesn't mess things up either. I would pretty well say that model is foolproof. Not anything like the styrofoam still air incubators with wafer thermostats.
Post problems pros and anything else that u liked about the incubator