Lexus, since 2007, has had a pretty nifty hybrid screamer out there with its GS 450h midsize luxury performance sedan. For 2015, the Japanese automaker (and Toyota subsidiary) adds an available F Sport sub-trim to the already capable Base trim, thereby upping the performance factor even further, while pampering up to 5 passengers with a few added bells and whistles. The F Sport variation, introduced in the non-hybrid GS 350 a couple of years ago, adds a bunch of upgraded suspension components in the hybrid edition, as well as some unique styling tweaks inside and out and a few extra techno-goodies. A brand new split-screen infotainment system with a 12.3-inch monitor boasting iHeart, Pandora and Slacker radio also can be delivered as an option in both the Base GS 450h and its F Sport sub-trim. Also new for the upcoming model year are the 18-inch alloy wheels that come standard aboard the Base trim, while up-styled 19-inch alloy wheels adorn the F Sport iteration. Of course, the 2015 GS 450h in either iteration is delivered with standard rear-wheel drive (RWD), but for those expecting to commute in wintry weather, both can be equipped with available all-wheel drive (AWD) to meet traction challenges. Power-wise, in a flip-flop of traditional performance factors, the GS 450h’s combination of a 3.5-liter hybrid V6 gasoline engine and a pair of 650-volt DC electric motors actually puts out significantly more power than does its GS 350 sibling’s non-hybrid V6. An electronic continuously variable transmission (ECVT) manages the gas/electric powerplant to the tune of 338 total horsepower and 254 lb-ft of torque. Additionally, look for driver-selectable Normal, Eco, Sport/Sport + and EV modes to adjust throttle response and shift points to suit your mood of the moment. Meantime, regenerative braking helps the V6 juice up the sealed nickel-metal hydride battery, while the ability to run for short distances on electric power alone (EV mode) results in mileage numbers running 32 mpg city/28 highway in standard RWD trims and 30/28 in AWD-equipped versions. Standard appearance features for the Base GS 450h include those new 18-inch alloy wheels as well as the return of a power sunroof and heated, reverse-tilt and power-adjustable mirrors. Inside, look for the Base trim to sport leather upholstery, heated power-adjustable front seats, full power accessories, cruise control and telescoping tilt-wheel steering. Bluetooth-interfaced Enform directions and connections technology, with an 8.5-inch screen, Remote Touch and Siri Eyes-Free voice-recognition gear, also returns for 2015, as do a heated steering wheel, memory for driver's settings, a remote garage door opener, an auto-dimming rear-view mirror, a rear-view camera and dual-zone auto climate control. Of course, all of this is embraced by wood, leather and simulated alloy cabin accents. Tech-wise, expect the standard CD/DVD player to return in 2015, again featuring 12 speakers, satellite radio, a video monitor and an auxiliary audio input (USB connections). The debuting GS 450h F Sport sub-trim, meanwhile, adds an adaptable sport-tuned suspension, 19-inch alloy wheels, upgraded leather upholstery and accent materials, a rear spoiler and larger brakes to all of the above. Alas, hybrid tradition once again dictates that the rear-mounted battery pack in the GS 450h cuts trunk space from the standard 14.1 cubic feet in the non-hybrid GS 350 to a still-okay 13.2 cubes in the gas/electric version. Options include a hard-drive-based navigation system that’s now complemented by the abovementioned upgraded split-screen capability in the 12.3-inch touchscreen. Further noteworthy available add-ons in either package or standalone form include a Mark Levinson 17-speaker Surround Sound audio upgrade, as well as Intuitive Parking Assist, a cold weather package, enhanced Enform infotainment with Smartphone apps, a head-up display and rear-seat DVD entertainment. Finally, standard safety features aboard the 2015 GS 450h include 4-wheel antilock brakes (ABS), front and rear side-mounted airbags, front and rear head airbags, daytime running lights, turn-signal-integrated mirrors and front fog/driving lights. Additionally, self-leveling high-intensity-discharge (HID) headlights and Enform emergency telematics also come standard, as do a post-collision safety system and a remote antitheft alarm. Available safety equipment, meantime, includes a blind-spot monitor, adaptive cruise control, pre-collision braking support, lane-keeping assistance and an upgraded antitheft system with glass-breakage sensors.