I've seen them worked over here Lennard. There's a few local to me and they were baying like hounds. No ferrets involved, just daytime mooching. They did get on to a big fox, but when they saw ivory they backed right off. They have caught rabbits, but they were pretty wild and didn't take much notice of the owner. Whether that's the dogs themselves or more down to the owner's failings, I couldn't say.
There was a good article about them in EDRD a few years back, working the stoney ground in Malta and the fact that they are bred for voice.