The original post below is dated so I will try to explain anew the problems with these devices starting with the wrist rest type (ie crampbuster and others)
At highways speed your throttle is rotated anticlockwise about 33-40 degrees. For these to work at closed throttle they need to be angled up not flat as shown in the promo photos. If you have them angled up at close its very hard to not accidentally open the throttle more then you intended as there is not enough space between the device the inner end of throttle.
Excuse this rudimentary drawing as I try to illustrate the problem since i have already sold the devices. The marketing that you fit them flat and then can hold the throttle open is not the reality. Your glove can get caught easy on the device and accidentally open the throttle more than you intended leading to an accident. Look at the photo below and imagine the device is pointing up at the sky, now there isn’t enough space to fit a large hand between that the switch gear case.
Hope this makes the problem with these things clearer – back to the original post now.
Both are small devices that affix to the throttle grip to sort of allow you to hold the throttle open by your palm/wrist so you can release your grip around the throttle and stretch your fingers for a bit. Both when installed need to be angled higher than horizontal due to the amount of rotation needed for highway speeds.
The Throttle Rocker is a good size and curves down on the inside left corner of the lever to interfere less with the throttle when you back off or are not cruising and coming to a stop. It affixes to your throttle grip with a Velcro loop which unfortunately just doesn’t manage to hold it in place for very long. So while it works slightly ok while fixed in place, no matter what I did it came loose.
I purchased the Crampbuster last month for my Easter tour and it is affixed not by Velcro but rather in the way it is designed. It is spring steel that you spread and push onto your grip and once fitted it can rotate up but never down on the throttle grip. That’s the good news. Unfortunately I found the Crampbuster often made me accidentally open the throttle more than I wanted when on closed throttle.
It is wide and you cannot fit hand between it and switch gear. There is a thin long version, perhaps this would be better. People say simply rotate the Crampbuster up and out if the way when needed and then return it into place however it clamps down really hard and it difficult to rotate is also trying to ride.
If someone sold one with the same shape and size of the Throttle Rocker but with the clamping system of the Crampbuster and little thinner then these just might work.
Theses sort of devices do offer you some means to relax your grip on throttle but are awkward. Still if you are in some pain touring then perhaps try one, the narrow crampbuster would be only one I’d suggest the wide one is not good at all. They are still a better bet than throttle locks in my opinion as throttle locks all have the bike either gradually slowing or accelerating. I have tried a couple and consider them next to useless.
Update, having tried many things over years of touring I have come to the conclusion that neither the wrist rests or the throttle locks offer me any assistance and I have given up on them. As of 2014 I have electronic cruise control and there is no substitute.