The LaCrosse is a sophisticated and thoroughly modern sedan. Quiet, roomy and luxurious, it offers responsive handling and a steady ride, qualities not normally associated with past Buicks. A 2.4-liter four-cylinder is mated to a light hybrid system which has good acceleration while returning an impressive 26 mpg overall. The refined 3.6-liter V6 (which we also tested) is smooth and delivers plenty of power. But the cockpit is a bit narrow, the dashboard is busy, and styling restricts visibility and access.