Looks like V2, HD and autocal(with additional device) will all tune.

Each product page is a bit different and I don't see any Product Comparison page.

What's the difference between V2 and HD?

What product do I need to tune/flash GM PCMs via my laptop? Data logging would be a requirement as well and it looks like they all work as a scan tool. Only question there would be; All the modules or just generic P codes?