ANY form of wheel spacer is about the worst thing you can do to a cars set up. (unless you are just using them in order to use a wheel with the wrong offset; and even then I wouldn't use them)

I just bought a set of x6 wheels with snows on them for my e70 x5. I still don't get why BMW runs a 74.1 on the front and and 72.56 on the rears on the x6. Just use the same size altogether already. Anyways, had to get some spacers/adapters the go from the 74.1 hub on the back of the x5 to the 72.56 rear x6 wheels. I didn't really want a spacer but that's the only way they come since your going down in size and 12mm is the thinnest they had. $75 with longer lugs on eBay for a pair. Deal.

For the "bolt-on" versions I will only use H&R since the German TUV verifies their designs. For the "bolt-through" style spacers the quality of the bolts is crucial, the spacers/adaptors are less critical as long as they are dimensionally correct.

At one point I used a set of 74.1 to 72.6 adapters (20mm) with hub-rings on the outside to use my OE 74.1 wheels....don't ask :-) Since they are bolt-through not a big deal.

ya the ones i ordered were bolt-thru version so I cant imagine they give me any trouble as long as the supplied lugbolts are good quality.

Sorry, yes I was talking about hub rings - I didn't see you were going the other way (small to big), yes hub adapters for big to small, just need longer lugs.