We had 2 cats for almost 18 years. We still have Bootsie, but she's 19 and failing. We replaced the carpet with a floating laminate flooring about 5 years ago. Cats puke and hork hairballs. It's what they do. When we saw all the dirt caught in the carpet backing, we swore never to have cats and carpet again. We will always have cats, hence no more carpet for us.
Midnight used to dash around the condo like it was a race course. She would dig her claws into the carpet to make high-speed turns. The first time she dashed around on the laminate floor, her claws slid on the floor and she spun out into the entertainment center. (This belongs in the thread on "Things You Should Not Laugh At.) She quickly learned that her pads had better purchase on the floor than her claws. After that, we could hear her little pads squeaking as she cornered.