PBR have been around for a long time now. If I am not mistaken they used to be australian company with australian made products. However I noticed that when I last bought a slave cylender it was made in asia. When I used it it didnt last long before the iron casting snapped in half. To be fair it looked like a total freak of a fault and normally they have a very good name for themselves.
Sorry I can't say anything specific about their clutches apart from a reasonably good reputation