i used to use them when i had my old vauxhall they didnt apper to be be as knowlebale as id expect a specialist to be, however i only really used them for mapping and not fitting i no other people who have used them for fittting and they seem happy, i belive most people dont like there customer service but i found it to be ok,
depends on the day and the guy working on your car i guess, every garage can make mistakes that people wont like or disagree with dont mean you wont find them usefull