I bought this when we decided to get a rescue cat and I didn't want it going upstairs. My husband was very sceptical - as he said "cats can jump"..and to be honest I wasn't entirely convinced it would work, but wanted to at least try. It was very easy to assemble, and we fixed it at the bottom of the stairs. We've had the cat for a week now, and he hasn't jumped it (touch wood..). It's easy to operate, the bars are close enough together that he can't squeeze through (although he is an adult cat and a kitten may be a different story), and although I have seen him eyeing it up, he hasn't gone over yet. It may be only a matter of time, but we're keeping our fingers crossed...I think in a doorway he might be more inclined to jump it, but the landing on the stairs is a bit tricky to judge and perhaps that is putting him off. Also, because the gate was there when he arrived he has never been allowed upstairs so maybe that also makes him less inclined to chance his luck. In any case, here's hoping it continues to deter him!
UPDATE just thought I'd post an update that, after 3 weeks the cat realised he could jump it, and that was the end of that. I have now bought a standard "no trip" stair gate and have fixed it above the babydan one. He definitely can't get over them now...