Upgrading the suspension will not solve the problem. Your experience on the E90 is coincidental. More sidewall is what you need. I'm a bit surprised to hear to flattened two tire and have yet to bend a rim. It is more common to have bent rims from rough roads. Are you sure you had proper tire pressure? More sidewall will definitely help. I would not replace suspension components unless your mechanic feels yours is worn out. It is easy to identify worn suspension parts. Look for leaks, cracks and any play in the bushings.

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