Hmmm...
What are these? As a drummer, these seemed interesting. I still need to get playing time with them on the kit, but from what I can tell (just beating on stuff in the house), I might be able to do some stick spins that I'm not really good at without these. The one take away (even if you don't want to spin sticks) is this. If you have any fear of dropping sticks during a show, then these seem to solve that problem. I'll update after I get some playing time with them.

Hand position...
My hands do like to slide up and down the sticks as I play and move between cymbals and drums. From just tapping on random stuff, this does lock you into one holding position. Would that make you feel trapped with your grip? Possibly. Would that make you feel more secure? Possibly. Only you know how you hold the sticks. Just beating on random household items, I'm kind of liking them.

Price...
The price is right even if they aren't useful. But I think they are.

Size...
I bought the #7 version which fits 7A and 7B sticks (as they say). I actually play with 8DN and these fit very well and are nice and snug. My 8X sticks diameter is really close to 7X sticks. So their size suggestions seem to be accurate. If you play with 2B, 5A, or 5B sticks, then make sure to get the #5 version (again as they say).

Installing...
You have to work it on the stick (from the tip) until you reach your desired position. If you overshoot your position, pull it off the back end and start from the tip again.

Extras... The rubber tips that come with this snapped right on my nylon tip sticks. They seem pretty useful for reducing the volume when you play. Rubber tips snapped on and off with the perfect amount of force. Well made.

Overall... These are pretty well made and study all around.
I recommend these, especially for the price. If you are up for experimenting and trying something new, then these might help you out.

I'm just starting my drumming journey and these have helped me already learn better gripping techniques and the tips allow me to play badly and not feel embarrassed by forcing others to hear my lack of experience. Worth it for me and allows for unimpeded improvement.

So easy to do tricks with

I bought this to aid my students in correctly gripping the stick at the fulcrum. I gave 4 stars because for the 2B stick I put it on, it was difficult to get on, and the silicone broke on one of them during the install. Over I think this will be a good investment, and I like the tips!

The "Drum Mutes" for the tip of the sticks, do not mute. I used them on my acoustic and electronic kits. I was afraid they would tear the mesh fabric on the electronic kit, so I will not use them on that kit. For the acoustic set, it make no difference in sound volume. The rings for my fingers woks well. I played for several hours and never dropped/through a stick. I like them as I am older and don't have the grip I used to.