I disagree with the above poster.
I have an Infiniti G35x and love it. Some initial problems with the Air bag system and front compression links which Infiniti took care of. Since then, knock on wood, no problems. Car is 2005, bought brand new now has 120,000 km on it. It is a TANK in the snow (I have Michelin Snow Tires on it.) Very much like the styling and engine. The one big bitch I have with my car is the 5 speed automatic, which has now been improved to a 7 speed. In 2005 the TL was not available in AWD. The new TL looks like shit in my book with that idiotic front and rear end and thus eliminates it from contention. Maybe Honda will smarten up and then the TL would be worth a look. For higher dollars, there is always the Accura RL which is available in the AWD, but it's fat, and slow, and not that powerful and kind of stodgy looking as well.
The Lexus GS is only available with the smaller engine (3.5 litre vs. the 4.6 litre) in the AWD format. If the GS was availabel with the larger engine, it would be allot better as the GS is a HEAVY car at 4,810 pounds vs. the Infiniti G37x at 3,700 pounds vs the Infiniti M45x at 4,100 pounds. Both the Infiniti models have more horsepower and torque than the Lexus and with considerably less bulk - could run circles around the Lexus.
Lexus GS 350 - 4,800 pounds with 303 hp and 274 lb.ft of torque
Infinit G37x - 3,700 pounds with 328 hp and 269 lb.ft of torque
Infinit M45x - 4,100 pounds with 325 hp and 336 lb.ft of torque
In short. the Lexus GS 350x is a fat, tired looking, slow, old man's car.
Hopefully Lexus has something radical coming out with a new GS.
I don't know if Toyota has problems with their AWD transmissions because the IS in the AWD format can only be equipped with the 2.5 litre engine and the Matrix was such a slow dog with the AWD that Toyota dropped the AWD version from its line.