Our 04 X3 doesn't have the servotronic and our 07 X3 has the servotronic. The difference is significant. The servotronic steering is very light at slow speeds it is also slightly lighter and more sensitive on the highway. My preference is to NOT order the servotronic but my wife would say just the opposite. If I were buying an X3 for the first time then driving cars with and without this option would be a good idea. I think this option changes the feel of the car a lot - much more than the sport versus non-sport. Again, partly because it is an SUV I prefer the more teutonic feel of the standard configuration - the turn-in is plenty quick and it feels like it tracks better on the highway - the later is very likely purely psychological.
2007 X3 3.0si - Wife's Car
2004 X3 2.5i - Daughter's Car
2003 K1200RS - Dad's Toy
2001 750 iL - Retired by me in 2005 - Great Car but wanted AWD
1995 750 iL - Retired by me in 2002 - Great Car