I was recently looking at the whole Mk7 gti / RS3 / M135i marketplace and ever since the first press videos of the RS3 I really wanted one.
I had the chance to drive one and was disappointed, then we started getting them in for tuning and had the opportunity to drive them a LOT more, but they never really exited me. But as a 4 door practical family car it was ideal.
I waited as they were still to pricy for my pocket and along came the M135i. Coming from a 500+bhp 135i coupe I really wanted one. Then I saw a 4 door with all the spec I wanted, ex demo M135i and bought it, without even driving one! And it's simply brilliant at everything, massive boot, comfy, quick, fun, very subtle and sounded easily as good as the Audi 5pot. Drives very much like an E92 M3 on the road and very revvy, doesn't feel like a turbo engine.
Then a customer with an RS3 we had previously tuned came back in for a remap re-install after a dealer visit had flashed to stock, what the new Audi software install had achieved was to shift even more power to the front wheels as a lame fix for the propshaft issue, this thing at stage 1 under steered badly enough, with Audis 'fix' it was even worse.
The M135i is far from perfect, steering feel isn't typical BMW brilliance, it's artificial and personally I don't like the brakes, but nothing some pads won't sort. I also think there's some electronic intervention in the braking before the ABS cuts in as I feel the braking being controlled at times, and not by my foot. (Still better than the over servo'd VAG feel)
As a tuner people would expect me to have gone wild with my M135i, but I haven't. It's not yet been tuned in any way, and a weekend drive recently made me think twice about tuning it for loads more power as it doesnt need it (others will want more, but not me. On the dyno it makes 350+bhp and 380ftlb already, I have suspicion it has a bmw software 'upgrade'of sorts anyway) maybe some work on throttle mapping (will try and make a linear map) and to smooth out a few niggles in the power curves.
But if the new S3 is similarly priced to the M135i, I can see it selling a lot, many people don't care about feel and fun but more about the other features that a 4wd car offers.