This is our third generation Roomba with the first one having brushes that were hard to clean with plenty of hair clogging the brushes, then the next one had the smooth brush system which worked much better. Now this one, is by far so much improved with me not having to clean the dust bin daily, and it cleans each room thoroughly where the other I had to take my other vacuum to get lists of areas that were missed. Plus the vacuum power is much better as this one is picking up the dog hair instead of blowing it around or missing the sections. The price was much greater so hopefully the price will come down so more people can enjoy the fantastic product. I feel blessed to have this product as it takes one of my tasks away. It takes longer to clean the house and is a bit noisy but is much more efficient than any of the other models that I have had.