The foil is a new model that has a bit more shape than the BT and a softer flex. The foils has a light and quick feel for a fairly wide ski. The BT is reasonably stiff and has a straighter sidecut. It does have a bit sofetr tail, but not to the extent of the old PR. I think the BT might be a better powder secific ski but the foil might be better for a light skier for everyday use.