I am by no means an expert, and would welcome comments from someone like Molakule, but here's what I do know ...
There are soap bases and other chemicals in greases that essentially give the grease it's viscous form and performance effects. Some of these are not compatible with others, and can cause separation of the base ending up in a degradation of the grease to the point where it can loose it's desired properties. I cannot comment past that, because I'm not a chemist.
So if one intends to take the wheel bearing completely apart, wash it all out, and install a new grease, then I'd say you can choose any grease you want. But if you intend to just "top off" the grease with a grease gun, then I'd recommend finding out what's in the bearing now, and only using a compatible lube. (Not needing to be the same brand, but the same soap base).
Where low-load and low-rpm applications exist, the grease differences may not matter (hinge pins, low frequency sliding contact, etc). But in high-load, high rpm (wheel bearings) applications, it could make a big difference; you could end up having a combination of greases that essentially break down and allows bearing failure at an inopportune time while traveling.
If you want to stick with OEM, then you'll have to call and ask what specific lube is being used, and then research it's base and soap properties.