My first reaction was, it has a CT 200h face and an LS side and read body panels. In the look department I think it can compete with BMW 5 series or the Mercedes E-Class.
Some of the new parts of the GS is the all new chassis along with reworked multi-link rear suspension. The interior looks more spacious compared to the current generation. Lexus also claims the new 3.5 liter V6 is putting out about 306 HP and 277 pound feet of torque. Currently the 2012 Mercedes E350 is rated at 302 HP and about 273 pound feet of torque and the BMW 5 series is rated at 245-hp with a turbo charge 2.0 liter with 258 lb-ft torque.
The GS comes with three driving modes, ECO, Sport, and Normal. It also come with an 835 watt Mark Levinson audio setup. It is also equipped with 12.3 inch display for movies, and other information systems.
Over all I think the GS looks great, it's too too far off the path for Lexus. It still has that Lexus quality and look to it. But this time around they just made it a little sleeker.