Back when I was a two cat household, I used softpaws for a while. On one of my cats, they worked great. The first time I put them on, they didn't stay on very long, because she pulled them off, but once she got used to them, they stayed on for as long as the company said they would, and things were fine.
But on my other cat, things did not go so well. With him, the problem was not so much one of them not staying on, but that they wouldn't come off. His nails were still growing, but they couldn't shed with the soft paws on, and the claws were starting to curl over to touch his pads. I actually ended up taking him to the vet so they could cut the soft paws off. They just wouldn't come off otherwise. It was not good. I stopped using them after that. I don't know what the problem was with him; if I used too much glue, or if he just didn't shed his nails 'right', but it wasn't a situation I wanted to repeat.
So, I don't know whether I would recommend them or not. You just might want to buy a set, and try them. If you do, keep an eye on the cat. I'd imagine you'll be able to figure out if they'll work for you or not after using one set.