Love the 300GT, 5 speed auto there is room behind me for a guy my height when I am driving (5'9") not quite 6' but plenty of room and no need to move my seat. Fuel use is less on the 300 than the 350. Is a 5 seater. Coupes are 4 seaters. Went for this sedan because of the kids. Interior in the leather is ok but the inserts are suede. Boot is big but not in the league of my VS commonwhore. After driving it for a year I don't think I would consider commodores now and they were my favs. Interior is the same as the M35 Stagea. Although the M35 is vast improvement on the C34 (89 Camry wagon on steroids) looks wise, all I talk to agree - Volvo. Wheras the V35 - Porsche (at least the front guards).
You can talk comfortably to passengers, (or to the handfrees from the back seat) at 100kph and be heard so not noisy. Bose stereo is great for a factory setup, great Bass, I won't be changing it.