Well, the TTS models are more expensive ... but the TTS leaves Audi TT behind with its engine ... it comes packed with a four cylinder, 2 litre, turbocharged, 265 horsepower engine with a torque of 258 ft pounds. It takes 4.9 seconds to hit a 60 mph for the TTS ... TT does that in 5.9 seconds.
Personally i would stick to the Audi TT ... the price difference is more than the modifications made to the TTS