The sinks themselves are that long, like a trough style? Or separate sinks integrated into those lengths?

No - not trough style. Dual bowl sinks integrated to those lengths.

I'm going only on my own recent experience with integrated sinks (Corian) on a long 105" vanity. Integrated sinks go wherever you want them in your vanity design - the countertop fabricator templates exactly where you want them and the holes are cut accordingly and the sinks are installed underneath if regular undermount or you choose the sink style you want and the fabricator integrates it into the countertop if it's something like Corian where it all the same material (which is what I understand integrated to mean). Is this not what you mean?