Wheel spacers

Has anyone tried these spacers . Not only 20mm but convert to studs aswell. The only thing I can see wrong is the studs are 12mm not 14mm diameter . Screenshot_20171015-090120.png
 
Also interested to see if anyone has experience with these spacers as i'm after a set of 20mm ones too.
 
Personally I would go for 20mm hub centric slip on spacers and convert to m14 studs and nuts

For 20mm spacers I'd use 90mm front studs and 82mm rear studs