I have not driven the Berrybrook demonstrator but did drive the demonstrator at Revolutions Morgan in Perth. The bevel box was not at all noisy. The brakes (which other threads have commented on) were a bit spongy at the top part of the pedal travel, but I drove it before the dealer had completed their PDI etc. and they said they'd be adjusting them...
Having never had a M3W I didn't find the lack of noise a disappointment. I think any 'car' engine will disappoint M3W owners!
The standard exhaust was ok - quite fruity near the top end but reasonably quiet at lower speeds. I might upgrade to a sports exhaust after a while but want some time with the standard one to see how it beds in.
