The 2nd BEST shifter feeling and gearbox setup available is a Tremec TR6060 with the Hurst Short Shifter Kit.
(the BEST is the stock >2009 997 GT3 RS but that's a Porsche with the mother of all gearboxes as well as the mother of all steerings)
Got that setup in my other car. It's a '09 Dodge Challenger SRT8.
Just as a comparison to our stuff. Watch this video here. You can exactly see how firm, precise and short the shifts are. And by the way: There's nothing cooler on the planet like a hurst shifter with the white ball.
I'd love to have that feeling in my BMW, too.