Ok I picked up my ABM300 from kevcooke today (cheers Kev !)- sampled it initially through a Warwick 211 Pro cab using a custom shop Warwick Vampyre NT5. It sounded anything but 'woolly' to me. Plugged my Stingray into it too, superb and bright sound.
Now then - I got it home and tried it through my MAG210 - sounded nice and bright again, I seem to be missing the woolliness ! Admittedly, neither of these tests were at gig volumes so it isn't a complete test, but I can't see it being majorly different.
Certainly there are brighter cabs available, but they don't sound muffled or lacking to my ears.