The fuel doesn't lock? It's not obvious by looking at it, but mine locks when the car locks (I figured this out one day when I tried to put gas in it with the car locked; I thought something was jammed). Maybe it's because I have an HSE Lux and the's not a feature of the HSE?
BTW, I came from an Q5 as well. The one thing I absolutely miss is the Bang & Olufsen stereo I had in the Q5. I bought my DS off the lot so I didn't have a choice about stereos, but I think I would have ordered the upgraded Meridian stereo given a choice (although the sound of the HSE Lux is not too bad; it's just not quite as "surround" as the Q5).