I have installed six pet doors (3 Ideal and 3 PetSafe brands) over the last few years. Two of the six doors were this large size Ideal pet door. I just replaced a PetSafe Aluminum door with this Ideal door because of a couple of added benefits.Both branded doors have an easy to follow installation template. Take your time and follow the directions and cutting a hole in your door will be less intimidating.My pet door experience goes back about ten years. My first install was a medium Ideal single flap pet door in a previous house. After seven years of great service the flap was getting ragged and since we had added a larger German Shepard to the family we opted to change to the extra-large Ideal Ruff Weather dual flap door. The dual flap door made a big difference in the temperature control in the small mud room and was in place for two additional years with no issues before we relocated. Once we moved we needed to give the dogs their freedom again so I got in a hurry to get the pet doors installed in the new house. Did not give much thought to the brand or whether aluminum or plastic, so I bought two aluminum pet doors. Remember I liked my plastic pet doors in the old house and had no issues with security or durability, so this where my pet door experience became more diverse.My install in the new house was the PetSafe large size aluminum pet door for a sixty and forty pound dog, on two exterior doors. The first door has a half window (nine panes) in the door with two inch blinds. The second door has a larger glass area (12 panes) with no blind. The first issue involves the space that is available above the pet door to slide in the pet door security cover. If you have a window blind on the door, the security cover will interfere, and you will need to raise the blind to create enough room to accommodate the height needed for the slide in cover. The tolerance of the aluminum groove for the slide in door cover is fairly tight which is a good thing for security, however you have to wrestle the blinds each time you want to slide in the security cover to keep the dogs outside. I tried to open up the tolerance but even after the groove was pried open slightly, I still cannot tilt the security cover (out) to a degree so the window blinds do not interfere. This means both hands must be free to install the cover. This does not seem like a big deal but it is something to consider if you latch the dogs outside each time you leave the house and there are kids and coats and stuff in hand. The second door does not have a window blind and I was able to open up the tolerance enough so the slide in cover would not interfere with the trim molding around the door window glass, but it is still a snug fit and it could damage the trim molding over time. I cannot say that this will be an issue for smaller size pet doors and this will not be a problem if you have a solid door.Based upon all of the issues I have experienced I will buy Ideal Ruff Weather doors for any future pet door needs. It is a plastic frame but it is substantial with metal screws and as it is quite a bit thicker, it sticks out on either side of the door about 2.2 inches. This does not bother me since this helps the insulation properties, and to overcome the clearance issues I raise above. Also the slide in security door can be installed on the inside or the outside. It slips into the groove snuggly in the beginning but loosens up and just drops and clips after a little use. This is so much nicer than having to have both hands free to manipulate the window blinds and line up the door.If you insist on PetSafe they also offer an Extreme Weather pet door that has a "clip on" security door. Cannot recall if aluminum frame but it is unique in that it has an insulated yellow flap in between two tinted flaps. Since the dogs cannot see through it they may require a little coaxing so they understand that it is not a solid object. Because of this the dogs cannot tell when the security door is in place. The side benefit is that our German Shepard slows down considerably going through the Extreme because she tried to come through at a brisk pace once or twice when the security cover was in place. I installed one of these previously as well and is a good product that insulates very well but you do have to kneel down and clip the security door on with both hands. And last, the plastic screws in the PetSafe doors are convenient for a quicker install but plan on replacing these with stainless steel screws once you establish the length.I think the only other issue is to address it from the dog's point of view. My dogs paused only slightly when we went from a single flap to a double flap. The smell (like new rubber floor mats) may have been a bigger deal than the thicker door frame. I also offer that smaller dogs that live with larger dogs will have to figure out the larger stride coming through the thicker profile of the Ideal style door. Not sure if it will be awkward for older and smaller dogs.Update 8/2013: Have purchased eight doors now and installed seven.Relocated once again and have purchased two more Ideal pet doors. One install was more complex because the door opening is through an exterior wall, so I hired this one out to a pro. We could have used the expandable tunnel offered by Ideal but the carpenter wanted a stronger box since it goes through brick. A simple box made from 2 x 10 boards worked well and made it very solid. Still very pleased with this product.