I agree, no-gi grip strenght is different. I can tell you rock climbing grip strenght training that will give you amazing grip strength. But it really doesn't translate to no gi except for wrist control. The best no gi grip strength training I have seen I learned from the guys at 10th planet St. Paul. If you have access to a heavy bag, gable grip around the heavy bag, lift your feet off the ground and hold for 1 minute. I have since added my extras based on rock climbing training. If you can hold for 1 minute, add a weight belt with 5 lbs. Continue to try for 1 minute. once you build up to 1 minute add another 5 lbs and repeat. I bet once you have worked your way up to 40 lbs or so, you will have a crushing unbreakable gable grip. Do the same process with s grip, and ball and socket seat belt grip. Check out Eric Horst's books and website Training for climbing and trainingforclimbing.com. His H.I.T workout is what this is adapted from. You want popeye forearms, this guy can get you there. You can also email him, he is a great guy and will be happy to help.