What kind of Ramshorn? Could you supply a pic possibly?
Common Ramshorns are one of the most plant freindly creatures in you can own. They can reproduce without a mate and will reproduce very quickly if food is available, but as CDawson pointed out. Tank maintenance will control them quite nicely.
Columbian or other large ramshorns will eat your plants, to some degree or another. As will apple snails. these larger snails don't usually reproduce without a pair though.
MTS's are also plant freindly, but reproduce much slower than pond snails and Comon Ramshorns. They are also much slower to clean up things but they will survive in tanks with fish that are known snail killers.