The short answer to both is yes.
Homografts (AKA allografts - aortic valves from cadavers) have been in use for many years. They last fairly well - originally longer than xenografts (AKA heterografts - bovine or porcine valves) lasted, especially in younger patients. They also didn't require anticoagulation treatment (warfarin, Coumadin).
However, there is a low level of immune system rejection involved in the use of a homograft, especially in the aortic position. After a dozen years or so, they have been described as being "like a lead pipe," rock hard and heavy. The current xenografts outlast them, which is why they are not often used for aortic replacements anymore.
However, homografts are more often used in the pulmonary position for the Ross procedure. And they often do cause a crisis at some point with rejection (usually in the form of the valve narrowing significantly), but they generally get past it and continue to function. For some reason, in the lower-pressure environment, they last much longer, sometimes for the recipient's lifetime. They are sometimes replaced with a xenograft, if replacement is necessary. Some surgeons do use xenografts in primary Ross surgeries, but it's not widespread.
My guess is that the xenograft would calcifiy more rapidly, as the blood is moving with less pressure, allowing chemical bonds (and thus deposits) to form more easily, a problem which shortens the life of tissue valves in the mitral position.
What effect the anticalcification treatments found on the newer valves might have on their use in Ross Procedures is uncertain at this time. It will be more than a decade from now before real data starts developing as to the treatments' effectiveness in more difficult conditions, such as chemically active young patients.
Best wishes,
