My dog door held fast until I got a Cane Corso who's grown into 150 lbs. He hits that door like a locomotive at top speed. Plus I have 2 other mastiff. I'm just now needing to replace the flap. I've had to tighten screws occasionally, and super glue a screw in. All in all it's held up very well. It does need to be checked for maintenance...like loose screws which if not taken care of will create more problems. I'm happy for it to have lasted as long as it has!
I am replacing this door after four years of use with two large dogs. The electronics still work fine, but often both dogs would try to jump through the door at the same time. Over time, this was just too much for the hinges. I will replace it with the same model. We are now down to one large dog and we really do like several of the features that this door offers. They could probably upgrade the hinges, replacing some of the plastic with metal, but if I must replace this every four years, I can accept that.