One factor to consider, most of the Craftsman sets are made from "alloy steel" and most of the HF Pittsburgh sets are made from "carbon steel". Alloy steel should be better, although the description is awfully vague.
I don't have any personal experience with that particular Craftsman set or any of the HF Pittsburgh sets. If I needed some inexpensive wrenches, I'd consider the Craftsman set. I'm more skeptical about "Pittsburgh" tools at HF as compared to "Pittsburgh Pro".
Carbon steel is alloy steel.
In fact all steel is an alloy. Steel is, by composition and thus definition, an alloy. Saying alloy steel is like saying that the glass of what I'm drinking right now is H20 water, not
just water. Redundant terms.
As far as the original question, the box ends are fine on these wrenches. Never had a problem and I used both the Chinese and USA RP wrenches for a few years (still have them, but I use Snap On DBE wrenches for mostly everything now, and have a few random sizes of some nicer brands).
The open ends (whether USA or China) are junk. The stock endlinks for the rear sway bars on Subarus you have to use a 14MM open end to hold the threaded shaft as you remove the nut on the other side of the bar. I live in MN where we use hundreds of pounds of salt per driver during the winter, and these get super corroded. You have to use an impact wrench backed by an open end.
It's a tough test for a wrench to pass. I've never gotten one off using a Craftsman RP wrench (gearwrench also has failed this test). I've done it with a Snap On FDP, Wright Grip, and SK so far (will try Proto ASD and Williams Supercombo the next time I have to remove one of these).
Plus, besides their function, they're ungodly uncomfortable and short. Can't wait to replace mine with a full set of something better...