Anyone any experience they can share?
Drag, efficiency etc.
I was thinking they might be worth a try for a laugh.

Very little drag, not great on a mountain bike as you can't pedal back to get your feet in the position you want! Great on a cruiser/pub bike though as don't have to have any cables making your bike look smmooootthh.
Can be had cheap as well. Sturmey Archer still do them iirc, through the Cycle Division, so any LBS.

Spent a morning on a city bike with one sightseeing in Stockholm. I'd forgotten how much of a hassle they are: not particularly powerful and if you're off-roading or even avoiding speedbumps / potholes it takes a LONG time to remember that you can't level the pedals unless you pedal them forwards, which you don't always have space to do.

I am not a fan.

: P

Used them on BMXs years ago when they came as standard equipment. Cheap and maintenance free but all you can do is lock the wheel with them so scrubbing off speed is a real pain. Difficult to use if pedals are not level and therefore crap in an emergency.

Did about thirty five miles on one last week in Spain on a rented cruiser. Easy enough for that type of ride, but no fun in traffic or offroad, which was a real pain. It was on a Sram three speed hub setup. I'd rather have a proper brake lever.

It's kinda like riding a fixie in that you have to ride in a more flowing manner, and skids are fun.

Not a great brake, but a good quality one is quite effective. I'd always prefer to have a front brake too, but I'd happily ride with just a coaster – only carefully.

Used a German bike with one for a few weeks for getting to/from work. I really liked it for that; mean't hardly having to ever use the front brake lever, which was the only other brake.

Almost crashed my MTB the first time I rode it afterward though, trying to slow for a corner 🙂

Great for skids

had one for a month in the early 80s
hate the feckers! 🙂

Thanks for the input.
Just considering them for a singlespeed dog walking bike. Seem really cheap and so may experiment.

my youngest has them on his Islabike. He thinks its amusing to back pedal when he's on the Trailgator 8)

Had one on my freestyle BMX. It was great for doing tricks when going backwards as you don't have to pedal backwards. Kind of miss it.