I have a black mystery snail that seems pretty low maintenence. I know that if your worried about it getting enough to eat then you can throw in some algae waffers and it will be okay. Personally mine just eats the left over fish food in the bowl for now, though i plan to get him some waffers soon.
As far as other snails go i'm not sure, my LPS only sells mystery snails. From the quick research i've done on them, MTS's seem like they can become more of a pest as they breed rapidly and once you have them theyre virtually impossible to get rid of. Evidently theyre hard to see as they mostly live in gravel and seeing them is usually a sign of poor water conditions. The same seems to be with ramshorn snails as well.
Nerite's on the other hand look like theyd be pretty good, from what i can tell. They are smaller and need slightly more demanding water conditions, but a couple things said that they can adapt to fresh water.
peace. love. & bettas.