I used to sell it back in the mid 80's - early 90's here in NH. We have a large in state only parts chain that sold( still? )it as their main oil, transmission fluid, and gear oil. Back when I sold it anyway it was nothing special and was actually, IMO, a below average product. The XLO diesel oils and the gear lube had some fans in the heavy equipment customer base but the transmission fluids and other oils were not so great and didn't sell well at all. Not to the shops and not to walk in customers. Never could understand why the company kept selling it because it just didn't move.
My info is a bit outdated however. Perhaps they are betetr now? I do know I would not use it unless I was sure they had improved quality.