It's important for mountain bikes it have them if they don't have a dropper post, I think.

Some designs aren't very good at all though. The ones that use a thin plastic washer aren't good enough for frequent use.

​​​​​​Salsa does sell the best QR I've seen. A price for quality. There are some good Bontrager ones too.

I'm sure there are many more good ones out there I don't know about. What are they?

And this reminds me, a dozen years ago or so I built a steel hardtail mountain bike for my wife and put a QR seat clamp on it. I bought an Azonic QR, which matched the color of the bike perfectly and was cheap. Well, it sinks, unless it's tightened with an Allen key, which defeats the entire purpose.

What's more depressing is that this bike is now on it's second dropper post and it still has that matching color QR on the collar. Pretty lame. Going to evict that thing today!

Thanks for the reminder!

A QR seat clamp on dropper post violates some sort of code I'm sure.

No pics in this thread. Sad.

Salsa QR clamp.

Now that the UCI has banned descending while perched on the top tube, droppers may now become de rigorous for the pros which will trickle down to the wanna be’s and conventional racing bikes.

Funnily enough I've just replaced the QR seat clamp on my mountain bike with a Nukeproof non-QR one. I struggled to do it up tight enough to prevent the seat slipping. However, I'm pretty sure that the clamp was as old as the bike, which is quite old and quite high mileage. It's a Giant XTC 4 which I bought used and I think, dates from 2006. I daresay a good new QR clamp would have been fine but I could see no reason to have one for myself.

I had noted that QR seems to be much more common on mountain bikes that road bikes. Perhaps people really do drop the seat before a rough ride but I've never bothered.

For my money they're less reliable than QR wheels. Generally wheels go into a vertical drop-out so they don't actually need a lot of force to hold the wheel in place - at least, with rim brakes.