I've only been pinched by this group once, Titan did it right after I got him. He was pretty scared though, didn't even leave the shell to do it. Just sat him on my hand and he grabbed on. Not too hard though. They all have their own personalities, some are very scared of people, others not at all, and everything in between. So it depends on the crab.
Honestly I don't hold them much, I hold them for pictures, to show to other people, to check gender, or to move them if I need to get at something in the tank and they are in the way. At those times I mostly just hold them by the shell. Of course the big ones can reach under the shell and reach my hand anyways lol. Too much handling can lead to stress in some crabs, stress can lead to death. I brought them to an elementary school once (my mom ran an after school program on pets) and let every child hold the crabs. I held their shells (people, children and adults both, have a tendency to rocket my crabs across the room the moment they move) and put their body in the kids hands. No pinching at all. They pinch when they feel threatened, usually new crabs do it, or crabs who are handled roughly. There is also a "security" pinch which is more of the crab just holding on, that one hurts much less and happens if you have an unsteady hand, like if you were walking with the crab and he was bouncing too much. You can always take them out and let them run on a table or bed, but make sure you watch them close, they'll walk right off the ledge.
Anyway, I love them, they are relatively active (way more than my leopard gecko), they love to climb and dig. The tank can also be fun to decorate if you get into it. Some people get really big tanks and go all out, water falls, filtered "pools", BEAUTIFUL forest like environments, vines, moss pits all over the place, second levels, etc. It can be really fun. I can't go all out like that at this point, maybe some day. They are NOT the throw away short term, super cheap pets the stores make them out to be. Initial costs can actually be quite high. Considering they can live into their teens or longer they really don't cost much at all long term.
Really interesting, fascinating creatures IMO, if everything is done right. With the wrong environment they are wicked sluggish, luckily doing it right is not all that hard. If you want more info I'd be more than happy to tell you what I know and give some links.
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