Nice Geoff...... I've just bought a 2.0 Z4 last week, 2005 model with low miles and am very pleased with it. Wasn't quite sure about the performance of it to start with but anything larger was ruled out by the insurance costs... a second car and therefore having to start from scratch...ouch! But the more I drive it and get use to the engine, it's actually not bad at all and as you say, the handling is great.
Yours looks like its got some M Sport bits on...the wheels and seats? I'm tempted with changing the wheels at some stage and your gear knob sounds interesting.... are they only available from the States?
Apologies if I should have introduced myself as a newbie before posting! Not got round to sorting out pics to post yet other than that I seem to have ended up with 5 BMWs which makes me sound a bit like a BMW junkie! Well ok............ three of them are motorbikes and the other is my main car, 320Dd M Sport Tourer.