that sounds like a bad way of doing it
extending the studs,could be opening yourself up for some real damage,,,,by doing this your creating a pocket,void,or space if you will between each stud,,,although the nuts fasten the rim tight to the studs,thats pretty much all,and with them being extended,weaken them further,,,,im assuming this style is merely a coller that fastens to each stud idividually
when you mount the rim normally,the studs secure the rim,pressing the rim against the hub itself tight,essentially making everything one piece,,,,not just to the studs,,the studs are just part of it
having the rim mounted at only four points (the studs) can bend,or break studs,,,or can warp the rim due to repeated jarring from normal use,because now you only have 4 points obsorbing the pressure at the rim,rather than the whole hub,the rim itself wasnt even designed to take pressure from 4 isolated points,,,,,, the studs themselves were not designed to be sole support,they were designed to be a fastening device to hold the rim secure to the hub,,,,,fastening tight is where the studs have there strength,,,,the suspension hides alot of the abuse the wheels actually endure
they make wheel spacers that essentially "shim" the intire hub out,,,they are solid,and fasten tight to your hub using the hubs studs just as if they were the rim itself,,,they have a set of new studs mounted in themselves that your rim mounts to just as if it were the hub itself,,,,by doing it this way it makes everything one solid piece again,with all parts getting equal support all the way around,and keeping all parts within the scope that they were designed for,and distributing the pressure,and abuse equally throughout
although the spacers you are getting may be considerably cheaper,are you really saving any money opening yourself up to damage by using them,,,,i can see where after using that style for awhile,repeated hard hits could,and most likely will create wheel wobble at the very least due to bent,or tweeked studs,,,or even tweeked,or warped rim
good luck,let us know how they work for you after using them for awhile,,,im real curious