I think they mean the ABR-1 tune-o-matic when they say the standard, they used to be used on les pauls, but now most les pauls come with the nashville.
This picture will tell you all you need to know about the mounting posts me and the freak have been talking about.

If you absolutely have to have a tune-o-matic, go with the nashville. It'll be less fitting time, less tape around the posts which must be good, and because of the chunky posts, it'll be better for heavier string gauges and down tuning.
Imagine if you tried to install the ABR-1, the choices you'd have is to wrap tape around the posts until they fit in the original slot (which would be a lot of tape and i don't think it would be very good), or you have to modify the original post holes by filling them with wood and then drilling the holes to accommodate them.