Well, I’ve been using these for years, and found ‘em to be the most convenient and of course result givers. I’m now back to my anaconda-like deadly grip.
“Caution should be exercised though from rubber heads like myself lie comfo on the sofa watchin teli, working the trainer - not to fall asleep while trainer ON in your palm. Nothing wrong though, except the discomfort in your arm when wake up, and slightly different expression of ones face during the nap - I’ve been told”.

I like the forearm trainer. It works well and would recommend it. The only problem is the intense rubber smell that other reviewers have commented on. The smell either fades or I just don't notice it anymore.

I've been playing with this at work here on and off for a few hours, and it feels like it is working. I am holding it with one edge against the "base" of my thumb, and my 4 fingers on the opposite edge (like a hinged grip exerciser) and it digs into my hand a bit. Not extremely comfortable, but not bad. I don't notice it unless I use it for a long time in one session. Also, this smells really bad. It smells exactly like a rubber dog toy at your local pet store if you'd like to "smell it out" and see what you're in for before you get one. My hand smells like it now as well. I'm still using it and I'm not going to return it—I just wanted folks to hear the negative aspects I uncovered.

Good for warming up the forearm muscles before climbing. Not sure how well it works for strengthening. They way you hold it at the distal joints of your fingers is not exactly the way you work your muscles climbing.

Great for when you're just sitting around. Conveniently small and simple.

Its light, works good for me.
Can be use for workout different fingers at a time.

This thing grows on you; you're sitting on the couch, and you start to instinctively reach for the blue rubber donut. You don't even realize you're doing it. Then one day you wake up and your forearms feel like steel leaf springs. Coincidence?

The forearm trainer is a wonderful tool and it’s portable too. It’s as small as the bottom of a small coffee can and is very durable as a compression exercise tool. I recommend this product if you are looking for a quick workout while between tasks.

I didn't expect much with this costing so little. The rubber smell discussed previously is kind of annoying. It smells like fresh tennis balls to me. I can feel it targeting the muscles I use to grip holds. I can see how it might cause problems for smaller hands, it is quite larger than I expected, but I'm really liking it after a little while of using it.

The forearm trainer was ok as long as you don't mind bruising your hands. I feel like if the rubber didn't burn my skin as much I would be much more willing to use it. Maybe it has something to do with the size of my hands, I don't know. Well, I wasn't very fond of it. I got a Gripmaster instead and I'm in love with it. Power Putty works pretty well, too.

Mine has lived in my car for going on eight years. It's a little dried out and flaky, but still works. Sometimes I'll do three sets of 50 for each hand on the way to work. If you use it too much it could be bad, just be careful and you'll be ok.

Might as well keep entertained with this little guy. Works well. Nice little work out to bring back the feeling of being a little pumped if you han't climbed in a few days. I find flicking your fingers does about the same.