well, yes and no. Many intact males are more vocal, but I have seen some that aren't. Duncan, my albino, was actually pretty *quiet* until his 3rd rut; now he's more vocal than he was before, but he's not as vocal as my others. Rocky is my biggest *talker*. I've been on the phone and people can actually hear him in the background; he's that loud LOL!
I have several European-blooded(and other foreign bloodlines) ferrets. Xavier is 50% English. Beau is New Zealand blood lines. Rockefeller is Swedish. Hunter is Australian. Duncan is half Swedish, half Australian and so is his sister Munchkin. Gamay Beaujolais is also part Swede. Majestic(intact) and Midnight(spayed), who are cousins, are both 1/4 polecat. The UK ferrets have outstanding conformations(skeletal and muscle), beautiful heads and faces, and gorgeous coats. They are extremely keen and alert--more so than your average ferrets. They seem to be "hardier", healthwise than other ferrets. And they are VERY high strung and active. I have known many UK blooded ferrets that are extremely skittish(due to heightened senses of hearing..or maybe their poley background, or both) who go into "defense" mode when startled and will bite.
The Swedish ferrets have never been known to have the nicest looking heads, but Rocky's is well proportioned. Swedes usually have plusher coats since many originated from fur farms. They also tend to be a little heavier in the back end. Even tho Duncan is only half Swede, he has a beautiful, somewhat longer than average(but not angora) rabbit-like coat(well not when he's in rut tho)
Hunter(Australian) has a backwards schedule--he gets his summer weight/coat in the winter and vice versa.