I have the SRAM X9 Grip shifters on my road recumbent bike. When I coast, which is rare, I cannot believe how loud the cassette is. Then, these grip shifters are just loud and clacky.

I could switch to triggers or bar ends, but the convenience on a tiller set up with the grip shifters is great.

It's really amazing that no other companies have come out with a grip shifter. There is literally no competition.