A once-peaceful seaside resort I visit frequently had become overrun with these things by late last summer. As I sat on a deck chair, not moving or doing anything which might cause provocation, a man walked past with one (thankfully leashed). It turned its head, stared at me with its horrible pink, shark's eyes and growled at me. It was a low, ominous, really threatening growl and I pretty much needed a change of pants.
They are unpredicatable, reactive, and as scary as hell. It's a travesty that now England and Wales have seen fit to deal with these menaces the irresponsible owners are now making them Scotland's problem.
And I'd say most owners of this breed were irresponsible. Responsible ownership entails chipping, neutering, not trimming ears, and keeping them muzzled at all times in public.
How many muzzled bulldogs have you seen in the wild? My answer to that would be none.