What i mean,is that the wheels you mean for 425,- are just normal one piece aluminum wheels
those you cannot compare with three piece magnesium light wheigts.
Please look at www.berg-cup.de and click on market place there is one guy selling just two centers for 500,-.
And there are two different sizes the 13 inch center which you can combine with 13inch 14inch and 15inch inner and outer beds
And then there are the 15inch centers (these are pretty rare)
those you can combine with 15inch 16inch or 17inch inner and outer beds.
The problem with using 13inch beds on 13 inch centers and 15inch beds for the 15inch centers is that you cannot disamble the tyre on or of the rim (those type of wheel called flat bed)
Here are some sites to look for some different sizes of rimhalves
www.sccspurverbreiterung.de or www.bbs-racing-wheels.com.
Let me remind you the rimhalves for the 15 inch bbs wheels can also used for ronal racing centers for the 13inch its a bigger problem because these are not the same
hopefullysome information to play with
greets skywalker
p.s if you have a set of magnesium wheels for 425,- for me please contact me im very interested