Club Obi Wan

H.S. Trask makes bison leather footware and sells 'buffalo butter' that claims to preserve, protect and condition all full grain leathers. I use it on some buffalo leather shoes and boots I own. I use it only occasionally, when my shoes need it, so I'm not sure of the long term effects. From what I can tell, it does all that brilliantly (even some mild water-repelling ability).

It is a pale yellow cream that has faint 'turpentine' (petroleum?) smell. Doe this indicate a relative of neat's foot oil?

Is all full-grain leather alike? Is Pecard's the best or a matter of opinion/what's on hand?