I was advised the eaxt same. I even talked to someone who is actually dragracing his 3dr. He also told me to stay clear of the "cheaper" coilover sets and advised me to buy adjustable Koni's instead. The "cheap" coilovers are for showpurpose only and deffo will give you the grief Mike just described when used hard. I also fitted Koni's because mine will be road car with the odd track-day aspiration.
I for one believe the problems Lee155 described are due to lack of maintenance. Koni's and crap are not two things you usually see together in a sentence, unless the word "not" is included in the same context. I do agree that the rear adjustability leaves something to be desired and the powdercoating is "somewhat" thin.