Has anyone used or have an opinion on the kits that allow you to turn your laptop into a automotive scan tool. I need one for my family's vehicles and for a friend who has an ongoing problem with his almost new car. I don't want to and really can't spend $2000 plus for a professional tool such as the OTC mindreader or snapon (plus software). I don't want a cheapo from the auto parts store either. Been looking online and there is a lot of choices. Just want the best one for the broadest range of (mainly domestic)vehicles and an interface to keep any electrical problems with the test car from messing up my laptop. Thank you for any info. John.