Rattles are most annoying, irrespective of the brand. I can get why Ed changed cabs.
Its probably an annoying speaker rattle rather than the cab itself. If these are hire stock, it's probably fair to assume that they've been significantly thraped. Guess that there's always the argument that the brand that survives in hire stock is testament to its build quality... but to be fair, give a cab to a meathead - and they will be able to damage it somehow.