I always thought the X5 3.0i was fine, I have had two of them and friends who had the 4.4i, I have owned a High performance suv (SC RR) and found it not that much better, I don't floor it from red lights or anything or use it to race but for freeway and city driving its just for me, it really comes down to indivigual driving style.

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The Present:
2014 Audi Q5 TDI Prestige
The Past:
2013 Lexus GS350
2013 VW Golf TDI
2007 BMW X5 4.8i LOADED & Loved
2009 VW Jetta
2008 VW Touareg VR6
2005 BMW X5 3.0i
2005 BMW Z4 3.0i
2004 BMW X5 3.0i
2003 BMW 325i
2000 Ford Explorer Eddie Bauer 4x4