The dwarfing effects of the rootstock will not have nearly the influence over limiting mass in containers as it would in the ground - container culture will naturally do that, and how efficient it (container culture) at keeping the tree small depends to a large degree on how you attend to the roots and your ability to keep the canopy compact by pruning.

If you live in ideal citrus country & will be growing the plant in the ground and need to keep it small, the plant on less vigorous roots would be a good choice, but for marginal citrus country (in ground) or container culture (across the board) I think the scion on more vigorous root stock would be my tree of choice.

The more vigorous tree would only outgrow a reasonable size container if you don't pay attn to biznass and let it, but the fact is, if you don't pay attn to biznass, the tree on the less vigorous roots will be following close behind in outgrowing the same size container.

Al