Hi I want to upgrade my c# driver to 2.2.3 ,previous driver I use MongoCollection class and this class have RemoveAll,WriteConcernResult,FindAsAll etc... features.To use async methods I change IMongoCollection and that time implementations change.Which class should I use?What is difference between abstract class MongoCollection and interface IMongoCollection.Should I select one, will MongoCollection be obsolete next releases?Or Should I use both

Thanks