This actually came up as a topic of discussion among some of the brothers who are York Rite during the Scottish Rite Reunion last weekend. Some of them pointed out that, in Texas, at least, one is only required to swear to defend the Christian faith. Then, another brother brought up a phrase in the Order of Malta, that has one referring to holding a belief that "the" savior of the world was crucified etc. or something to that effect. Rendering the Knights Templar part of the York Rite technically prohibited for non-Christians unless you use some major rationalizations. It was also pointed out that this is not the case in Canada.
That said, the other bodies of the YR are open to all (regular) masons of any faith. Personally, the complete openness to faiths, and the depth of the philosophy in the Scottish Rite were what drew me most to it. I honestly have no real interest in pursuing the YR.
Both rites have a Royal Arch degree, both have "Templar" degrees/orders.