Dinan's products are great but they are expensive and in many cases their performance gains are on the conservative side compared to the competition.
The best thing to do is research all the alternatives and see what works best for you.
15' Msport X3 28i _Mperformance - ACschnitzer - H&R_
15' Sportline X1 28i _Mperformance - H&R - Recaro baby seat_
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