I have two kids, a 4 year old and a 2 year old. When our 4 year old was little we kept him safe by using the Super Yard as a perimeter in the living room. It was nice because I could leave him to put away clothes, do dishes and shower. On the other hand, he REALLY suffers because he has little impulse control. He has a really hard time when he isn't supposed to be touching something and was a runner anytime we went somewhere. Now I think SOME of it is his personality but after having a second and doing traditional child proofing I an tell you that at 2 years old he listens much better and has far more self control than my 4 year old. I really think it was because he had to learn early on that there were things he couldn't touch, climb on or get into in the house. Where as, my 4 year old never had access to anything but his toys. For instance, my 2year old had to learn not to play in the plant dirt, not to touch the buttons on the tv, not to get into the DVD cabinet, etc. My 4 year old has some what caught on, he's smart enough not to run off at the park now because he knows about strangers and he won't touch the stove because he now understand the danger.
But all in all if I could do it over I would do it with more traditional methods.
Don't get me wrong the gates have their place, their great in the back yard to put around the BBQ so the kids can't get to close, they're awesome for camping, we made a large yard so the kids couldn't wander off and we could sit down and relax.
Hope this gives you an idea and help you out. :o)