the way it works is this. If the spacers you require will be enough to prevent the wheel centring on the lip on the hub, then you need hub-centric ones. If they arent, then you dont!
There are a few variables to consider, the thickness of the spacer vs the ammount of hub lip you have is the most obvious one, next you need to check the centre bore lip on the wheels you have. For example, 10mm non-centric spacers were fine on my TSW omegas, when fitted to my MK2 Golf.
But the same spacers and wheels didnt fit my MK1 cabby,m becasue the lip on the rear disc wasnt quite as deep as the lip on the rear disc on my MK2, that combined with the taper on the spiggot ring on the TSWs meant I couldnt centre the wheels on the cab, but they centred perfectly on the MK2.
Also, if you wnat hub-centric spacers these have to be deep enough to fit over the centre hub on the car, otherwise they wont fit flush. For the same reason the non hubcentrics were fine on my MK2, hub centric 10mm spacers didnt fit as the centre lip was too deep, so they wouldnt fit over it. The very same hubcentric spacers would have fitted on the cabby as the lip is more shallow, but I bloody sold them
