When we were at the Nring last year I had the 10mm spacers installed on the car . Everything was very OK so I'm justing thinking to put them again when we go to Hring (even if I have now the TD's, I think will improve stability, when first I put them I could really feel that)
The spacers were bought from mtm and they have assured me all will be ok, they will not cause any extra stress anywhere because they are too small.