We selected the X3 i2.8 at the end of our 2008 335 Convertible lease.
You might think that after driving at 335 the X3 would be a disappointment; on the contrary, it's a much nicer car to live with.
The 335 was fun, but somewhat impractical and had a very rigid ride; the X3 is surprisingly smooth and agile.
We chose the 2.8 because, frankly, we had problems with the 335 engine... had to tow it back to the dealer with less than 20K miles.
The 2.8 has plenty of power for "real-world" driving.
It is smooth and sporty.
The interior is quite large considering the external size of the the vehicle... especially the rear seat (compare it to the Mercedes GLK350).
The sporty yet smooth drive; roomy interior for the size of the vehicle; gas mileage (22.5 combined); cool sunroof.
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