I'm considering obtaining one of these. I understand that some are vehicle specific but others can be used on a variety of cars. I'm thinking mostly of our 2007 Cayman S but we also have a Mercedes and a couple of Toyotas. I'd much rather be able to diagnose on my own and not fall prey to unscrupulous shops or dealers.
Does anybody have a favorite or can suggest one? Again it has to at least work on the Cayman and hopefully the Benz.
Thanks in advance.