M5 or 996

I'm presently the happy owner of a 99 540 with sport package. To date this has been the best car I've owned. I chose the 5spd steptronic automatic due to the amount of driving I conducted. Unfortunately, a great deal of that time was spent in traffic (I live in L.A.). Anyway, my commute to work has been drastically reduced recently and I'm in the market for a new car (i.e. one with a manual tranny). The 6spd Porsche 996 with the factory Aerokit (basically looks like a GT3) is my current choice. The problem is that I've truly enjoyed my BMW. Furthermore, the enthusiasm expressed by the posts on this forum have made me take a second look at the M5. Now I don't want to start any war of words, but for arguments sake lets assume that both cars boast similar performance figures. So here's my question: Does it seem a bit odd driving a 4000lb 4 dour sedan with a manual tranny? Every car that I've owned, with the exception of the 540, has been a two-seater sports car with a manual. It just seems that manual transmissions belong in smaller compact sports cars. Please help do away with my concerns as the M5 seems oh so sweet.

Safe driving to all.

Tate