As one of the true mid-size sedans on the market, the 2012 Buick Regal splits the difference between smaller compacts like the Volkswagen Jetta and even the brand's own upcoming Verano, and larger sedans like the Honda Accord and Hyundai Sonata. It's in a niche with similar four-doors like the Nissan Maxima and Acura TSX, which means some shoppers will find the rear seat accommodations and the trunk a bit small.
The Regal's front seats give the driver and passenger enough room to feel comfortable without being constrained. The leather-topped driver seat is a great place to work the Regal's controls, and power tilt and rake can dial out the bottom cushion's flatness. There's a bit less head room and leg room than in the big four-door family sedans, though, which means you'll sit a little closer to the available sunroof, with less room to back the front seats up before cutting into rear-seat space.
The back seat is relatively spacious, and rated for three passengers, even though two adults are the most you'll want to put back there. Leg room is similar to that in the Honda Accord, but something about the cushioning in the Regal makes the back seat seem less spacious--while it's still about three inches more generous than the same space in the Acura TSX. For sure, the roofline meets more heads than in taller sedans, but it's comparable to truly large four-doors like the VW Passat in that respect.
Cargo capacity isn't the Regal's strongest suit. With just 14.3 cubic feet of trunk room, it's about 3 or 4 cubic feet smaller than other sedans, and a piece of luggage less than the enormous 20-cubic-foot trunk in the Ford Taurus.