Close to pulling the trigger on 09 3.0 . . .

[E70x5]

Hey everyone, NEWBIE here. I'm close to buying and '09 3.0 18k $47,000. The truck is pretty loaded with : prem, tech, cold weather, rear climate, third row, and confort access. The truck was originally $50,900 and went on sale for $47,989. They offered me about 500-800 less on my trade compare to others but came down to $47k even for x5. It was also a corporate fleet vehicle. IMO, 18k in 11 months is a lot of miles, and what exactly is a corporate fleet vehicle ? Also what are the major issues that affect the '09's ? I know I've read something on here about cold weather piston slap noise. And also "too sensitive accellerator" but I think it was for 4.8's. Are there any others issues 09 owners are facing with their vehicles ? Any input would be greatly appreciated . . .