BMW replaced the timing chain guide in the N20 engine used in the 2014 X3 28i with an improved design beginning 1/2015. Unless the timing chain guide was replaced with the improved design in the 2014 X3 28i you are considering, you should investigate timing chain failures reported by owners. Another point to consider is whether the Dinan added boost in the X3 28i may put additional stress on the timing chain components during repeated hard acceleration. Will the warranty cover major engine damage due to possible timing chain failure for the entire period you plan to own this vehicle?
http://www.rightfootdown.com/cars/au...nents-n26-too/
https://bmwtechnician.com/2016/08/07...g-chain-issue/
http://www.bimmerfest.com/forums/sho...d.php?t=957634