Williams USA from Tools Delivered
It will probably be hard to beat those for quality / price ratio.
Almost half price for Williams version.
http://www.toolsdelivered.com/Willi...ools-3-8-Inch-Drive-Chrome-Metric-Socket-Sets
What is the difference between Proto and their Blackhawk line?
Blackhawk is kind of like what Williams is to Snap On. Though, Williams is an industrial brand, as is Proto. I think Blackhawk is just a cheaper made tool, used to attract a different customer base. The reason I compare it like that is because Williams has USA made and Taiwan made, just like Blackhawk has.
With that said, I used Blackhawk USA wrenches today to install hydraulic lines on a tractor. They get the job done just the same as my Snap On's...
I also purchased 3 different sets of Blackhawk USA by Mac when Mac had a sale on them online. Same as Proto. All under Stanley umbrella. They are excellent quality. Deep broach, great chrome, engraved sizes. Perfectly made sockets IMO.