Choosing inside the Biofinity range is mostly a matter of matching the box to the prescription in front of you. Eight versions are listed here, and the names describe what each one does rather than how it feels.
XR exists because a standard box only covers so much of the prescription spectrum. If your power, cylinder or add value is high, the XR box may be the only one that carries it. Distance dominant and near dominant toric multifocals are ordered as a pair, one designation per eye, and which eye gets which is decided at the fitting, not at the checkout.
Contact lenses are prescribed in the United States, so we verify a current prescription before an order ships. Check that the name on your prescription matches the box exactly, including Toric, Multifocal or XR, since those are separate products rather than options inside one. If anything on the prescription is unclear or abbreviated, the practice that wrote it can confirm it faster than a guess will.