The SVT-VR heads are meant to be great, but I have heard a few shit stories about them. They are designed to look like the the original blueline SVT's but they don't sound anything like them, probably something to do with the fact that the vintage ones had Mullard valves in them. They also have this stupid "tube protection circuit" which means that you turn the amp on and it automatically clicks off standby for you, but there were A LOT of people in the states having problems with theirs as it wouldn't come off of standby AT ALL. But in saying that, apparently, its really easy just to wire passed that part of the circuit.