Just saw this thread. Noticed you decided to stick with the stock header, and that's fine. I have a 2008 Mini Cooper S Convertible, but it is heavily modified to spec out near or above the performance of the GEN 1 Minis. Luckily (or unfortunately), I needed to replace my header last year, so I gutted the whole thing, took the plunge, replaced the header and exhaust. I did go with the RMW Shorty header, but also added the JCW exhaust. I could have gone with Borla or Millitek, but I'm actually glad I did not. The RMW Shorty Header adds noticeable power, but does pack on a little extra noise. The JCW exhaust, while powerful in its own right, does a decent job of restricting a bit of the noise to give it a more...."throaty" sound. Idle is nice, and the first 2-3 gears produce the loudest resonance (and best pops on the downshift!). Despite the added noise, I don't regret the modification one bit. Again, apologize to be so late to the party on this post. Just more food for thought, I suppose.