mmm further research certainly required.. My daily drive is up the M3 and back again, so not thrilling etc...
In that case the Koni FSD's would be perfect for you. Their selling point is the fact that they offer superior comfort when driving normally, better than standard by all accounts, but then when you're going for more of a spirited drive they firm up automatically and offer the road holding and damping you need. FSD = Frequency Selective Damping I believe. Clever stuff.
So in your situation, pottering up the M3 each day will be smoother than it is now... but when you decide to take the scenic route home to have a play, it will perform better than it does now too