The diesel sky active engines indeed have low compression ratio but both diesel engines have twin scroll turbos (seems to be fashionable just like all new BMW's ). This will mean access to the usable power from idle with first turbo before the second turbo kicks in at about 2,000rpm. It's all sounds good. Just a shame that they haven't thought about turbo charging their petrol engines with twin scroll.
Also they have the sky active gearboxes as well, for the manual it's a short throw gear change just like the MX-5. As for the auto this has both normal clutch as well as a torque converter!!! Basically non of that slippage feeling of the engine when accelarating on motorways as clutch keeps things locked up. I can' t wait to try one of these to be honest