Yes, SMG can shift up and down for you, if you put it in auto mode. In manual mode it holds a gear until you shift, and the electronics protect you from shifting when such a shift could cause damage (ie downshifting at 6000 rpm).

All that aside, driving an SMG is not really like driving a conventional automatic, even if that auto is a steptronic, or has paddles. The transmission accomplishes the same thing, but in a very different way. An automatic has a torque converter, and the shifts are very smooth. An SMG can be that smooth, but only if you pay attention to shift points and throttle. It is a manual transmission, with a clutch, but the clutch is electrohydraulically actuated.

Hope all that helps.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue