Agreed.Some readers have better interfaces, i.e. better displays and more appropriate code descriptions for Error Codes based on your car.
I do think that there is a difference. We'll likely be carrying OBDII Readers that are the best fit for the Maserati we've found... keeping the price in a reasonable range of course. We do have some in stock now that we like but I'm going to do a more exhaustive search. I don't recommed the PC based systems for most owners, it's much more convienant to have a self contained unit.