This is the tool I use on my VW's, I don't know what you're working on, but I used it on my dad's Blazer to open up the calipers. It's the first tool listed on that page.
http://www.metalnerd.com/cat08.htm
I'm doing 15,000 mile changes on my VW TDI. I use Blackstone for my testing as well, great people to deal with and VERY knowledgeable about what the results mean and what to look for.
I am in desperate need of larger metric wrenches from 24-32mm. I have a lot of older Craftsman SAE stuff that I have no use for since I work on VW diesels.