I am having trouble envisioning a gig that would need 3 or truly benefit from 3 Barefaced cabs. Wanting three, enjoying three, okay... totally get that. Needing, I just don't see it from personal experience with the BF cabs. Of course I don't play 130 dB thrash music, so YMMV. Just my BB2 covers 90% of all gigs I do, and really I think the SM alone would cover at least 80% of what I do; the SM + BB2 is my overkill rig, though I confess to enjoying it even when it's not needed. Of course you did not say you "need" 3... so I chalk you up in the "want/enjoy" column, which I fully empathize with.
To run three, of course you'll want to pay attention to the ohm load. 2 Barefaced cabs running at 4 ohms is a lotta juice when paired with a good amp.