I think too many o rings for suspension is not suggested, especially if you run in bumpy and dusty tracks. Why ? First of all, you reduce the volume of oil inside ( the plush feelling is gone ). Secondly, you need some droops to make the cooper stick to the ground and feeling stable during cornering. I suggest to use Tamiya shorter spring set OR simply remove the adjustable collar so the front and rear suspension could have some droops ( droop = the amount of shock collapse as soon as the tires touch the ground ).