I've been using this swivel cushion for a few weeks now, and it's been a mixed bag. The 360° rotation works best when I'm not fully seated - perfect for those quick in-and-out moments in my SUV. My mom, who has stiff hips, finds it much easier to enter/exit the car now.
The memory foam does provide decent hip support during rides, though I wouldn't call it plush comfort. The anti-slip base works well on fabric seats, but on my leather bucket seats? Forget about it - this thing slides around like it's on ice. And when I'm actually sitting on it, the rotation feature becomes useless - the cushion just compresses flat.
Where it really shines is for post-surgery recovery. After my knee procedure, that smooth rotation saved me from painful twisting motions during transfers. But be warned: if your car seats aren't perfectly flat (looking at you, sport bucket seats), this might not work as advertised.
The lightweight design makes it easy to move between vehicles, though I'm still skeptical about how well heated seats would work through the cushion. For $40, it's solved some mobility issues but comes with enough quirks that I'd only recommend it for specific situations.