BSbullie mentioned before that even the dwarfest of trees such as the Pickering can reach 20+ feet with enough time, but trees like you just mentioned can be pruned and kept in a container with regular maintence.
I'm going to try to keep Maha Chanok, Pina Colada(because it grows so damn slow!),and Pickering in a container and gradually uppot them to a box size container, however, eventuall I think there comes a time when the tree can no longer be productive with good quailty fruit once it has gotten so big with a larger root system than it's container can hold, at least that's my assumption... so I'm thinking after about 8-10 years it would be a good idea to have another graft of that tree already growing and ready to replace it.