AC Schnitzer has prepared two production ready concept cars for this year's edition of the Geneva motor show. We've already told you about the first car, the diesel-powered 99d that is based on the BMW Z4 roadster, so here's the tuning firm's second proposal. The ACS5 Sport S Saloon is based on the latest BMW 550i sedan and is said to feature numerous performance and styling upgrades, though AC Schnitzer is keeping mum about most of the details. Read more »