Snails and cherry type shrimp usually get along fine. But you do have to be sure to watch the water parameters, as the shrimp have far less tolerance for ammonia than the snails do.
If you're feeding the snails, they can allow a fair bit of food to sink into the substrate.. I had this happen recently in my snail tank.. lost a couple of shrimp, when they got caught in bubbles of swamp gas that was coming up from underneath the substrate. It's basically anaerobic bacteria decomposing the left over food, which can generate toxic gas, like hydrogen sulphide.. Just something to watch out for.. otherwise, they need similar water conditions and shrimp will even pick algae or other things off snail shells. The snails don't seem to even notice it.
