You have really not looked into this

The RS is a massively re-worked lump. It really is very very different! The bore liners go on the St engine over 300bhp. Lots and lots of threads about it on the owners site. Was looking at them myself and got put off.
The 2.0 tfsi won engine of the year 3 years running and will see over 400bhp with ease before any strengthening is required. They are slow compared to most cars. Its a heavy car with not much bhp for the engine size. 2.5 litres and thats it
