I've seen a few shouts for this event and every time I try to get in on BST people tell GTFO or bring a real DD job. Now, I'm a little confused. The vast majority of the mobs are Easy Prey-Decent Challenge and and bst pets deal very impressive damage on these foes. I did a few trials on the test server and Tiger hits the EP-DC mobs for 250~300, crits for 400~+500, Ruinator does 1800~2500 with the odd spikes of +3k. As to be expected, those numbers fall off on NMs like Chariots and such but tiger was still doing 200+ on melee and 300+ criticals. BST also means less healing since pets take the brunt of attacks and they are unaffected by things like gear wipe and charm, which some of these NM like to use.
Was unable to try bst on the Boss Floors, but I would be really interested to know how a Group of 2~3 BST with proper support would fair in this event.