I have the X5 50i MSport with AD. The difference is subtle but worth it in my opinion. It would take back to back drives over the same roads to know whether the non-AD leans towards the soft setting or sport setting but having both choices is nice. I wish the button did more such as steering or throttle response as in other models.

I'd recommend active steering even over AD (I think). Without it, parking lot speeds is very heavy. With it, parking is a breeze plus low speed corners have less steering turns, quicker than my Z4. Unlike test drives of older cars with it, I've not been bothered by the changing ratio as speeds increase.

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Richard
Sir Snaps-a-lot, 9 Time Dragon Slayer (54 runs!)
2011 X5 50i Alpine White, Biege Nappa /Lt Poplar M Sport
2009 Z4 35i, Black Sapphire/Ivory-Black/Anthracite

Gone but not forgotten: '08 550i, '06 X3, '06 650i, '02 M5, '99 540i