For GM, the Tech 2 is the top choice. $3-6K depending on whether
new or used and how many add ons you get.
In the aftermarket, Snap-On MT-2500, Modis, Solus, Solus Pro,
tons available on e-bay for a fraction of what they cost new.
Laptop/PC based, Auto Enginuity has the best bang for the buck.
The base OBD2 package +GM enhanced runs about $400, so far no
charge for updates.
Avoid anything made by OTC unless it's dirt cheap.
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