Audi S4 or BMW M3?

Hi,

I used to own a 330ci (2001) and loved this car, I fancied a change though
and for the last 12 months have owned an Audi A4 3.0 Quattro, also a very
nice car but not quite as fun to drive as the BMW.

Now I'm looking at changing and I can't decide on an M3 or an S4, I've
driven both a while back and I favoured the BMW, seemed like a more
aggressive drive and had a lot of brute force.

But now when I look inside the BMW it all looks very dated, suppose that's
why they're changing the 3 series, even if the Coupe / M3 won't be out until
2007 :-(. The Audi looks a lot more up to date but I don't know if the S4
is available with the face lift yet (do you know when?)

Has anybody owned both these cars, any advice would be welcome!

Thanks

Daz