As I said, I sold (and my employees installed) carpet for number of years. I can tell you that ANY carpet WILL fuzz (berber-closed loop less so) with ANY vacuum that has even moderate amount of agitation.
The fuzzing will stop once the carpet "wears in". Still,....I don't recommend berber in any house with pets. Spending money on top end carpet is not wise with house populated by pets, babies, toddlers, etc. Regardless of how well they are trained, accidents WILL happen. Berber is extremely hard to wash with extractors (and they also agitate!), because the twisted closed loop yarn retains/absorbs a lot of liquids, and holds them.
Since I have four dogs, and three cats coming in and out, I opt for moderately priced , cut pile carpet, that can be washed MANY times, and replaced every 3-4 years without breaking the bank. From my avatar you can see that certain areas in my home are covered with area rugs. If the accident happens on the area rug, I take it outside and deal with it. My animals are extremely well trained, and I still deal with 3-5 accidents a year.
Oh, and just to add,......Kirby "Rug Renovator", "Carpet Shampoo System", or whatever they call it these days, is totally USELESS on spills, and/or "pet accidents". Works well on dirty carpet from the normal foot traffic, but doesn't do anything for the spills.
Some of the posts above are right on the money in suggesting mild (non motor driven) agitating brushes. I know what kind of challenge is to select the right carpet/machine combo, in accordance with the living habits.
