Do you guys drive in standard "D" or "S" mode?

[rmani]

When I had my 7 series I was told to always leave the car in "S" mode unless on the highway. This basically prevented the car from shifting into 5th and prolonged the transmission life.

I'm curious if you guys do the same thing on the X5s. I never shift the thing manually but if I push the stick to the left it puts the tranny in "S" mode so for around town driving that's what I've been doing since I've read the transmissions are the weak link in our cars and I want to do everything possible to prolong my transmission's life.

Any input or insight you guys can offer would be appreciated.

Thanks!