There's one thing more effective at killing escorts than Assault Boats. That's Fire Ships. Yes, those little transports that are filled with SuperNapalm (Do anyone use these?) If they make it through intact, they instantly blow up escorts in 3D6 range. I don't think you can BFI for this, now can you? Imagine two squadrons of five Hellebore frigates (750 p.) flying close to one another, when a Great Flame Ship Of Doom pops out and blows up, taking all ten out...what an I saying? I play Eldar! (And who would spend 750 on Hellebores?)