I agree that LO is more polished; it is also a little more woody and smoky to my nose. As hedonist described, it smells like burning oud chips. The Montale is an oud in the mold of the other ouds in the brand, but with leather and animalics. They are both powerhouses and have both great sillage and longevity on me.
If offered, I'd go for one and one. Indeed, I own the Montale already and have a big sample of LO, thanks to a kind BNer, which will likely be upgraded to FB. If I were forced to choose between the two, it'd be a hard decision.