i can vouch for workshop X and person abc. My frens and i take our hondas out to track and the cars perform extremely well, and the cars are tuned by person abc.
Thats the biggest test there is, being vouched for by customers themselves and not some workshops that obviously plant some people in forums.
I have a feeling that sometimes we have to look at ourselves when we have unhappy experiences with workshops. Personally, for myself and other frens, going to workshop X means we can be sure that even if we are not happy person abc will help us out somehow.
vti-2 edit: removed workshop and personal names