Have owned this car for 2 months and can report that it does meet the gas mileage specs if you are light on the gas pedal.
In addition, the interior is very nicely done, the climate control is excellent, and the seats are great.
Exterior styling is also excellent, with many positive comments.
I bought this car becauseI could not find a Lexus, Acura, or similar with good styling, good mileage, and a reasonable price.
Great driving, comfortable car with loads of features. Problem is the lack of quality control at the production plant. Car came with some minor paint imperfections, side mirror and window molding installed incorrectly, and not to mention the front fender and trunk lid having large gaps. GM did have the dealer,Todd Wenzel Buick repair the paint and the window molding. I now have a new car that has mis-matched paint, tape lines and sanding marks that can be seen through the paint, expected and was promised better. Three trips to the body shop and hours on the phone, car still looks like a terrible. GM is not interested in quality at this point and are unwilling to stand behind their product!
I'm about to wrap up my 24-month lease. For the most part, I'm happy. What they say about this Regal (nee Opel Insignia) being unlike Buicks of lore is true. Handling is precise, ride is firm (in a good way), interior design is clean, all very European. And it looks fantastic, especially with the 18" or 19" rims. Content is good too, for the price. Now, the issues: first, the mileage for the eAssist hybrid I have is WAY overstated - I drive 70% highway and never get more than 24 MPGs. Lack of power and harshness in non-Turbo engines is noticable. Quality control still has a way to go, e.g. paint flaws & loose trim. If I had gotten the turbo or GS, I'd rate it a solid A. With the hybrid, B+.