I can tell you what not to buy, Grayston. I haven't got an issue with the principle of wobble bolts, if the quality of the bolt is the same as the oiginal bolt. Grayston are turned from bar and not forged as fiat bolt. The strength is not comparable
Is there not a solution such as buying a hubcentric spacer that you bolt onto the hub with existing bolts (so it has holes for the 4x98) but it also has holes that you screw the wheel on or into (once the spacers are bolted to the hub) at 4x100?
i have run wobblie bolts for 2.5/3 years now with now problems at all and a mate has snapped 3 fiat bolts in that time , i know what i'll be staying with