A few months ago I spent a significant portion of my life going through an obsessive wrench comparison. After asking questions here, I drove from store to store buying wrench sets and comparing them, including:
NOS SK sets (Ace Hardware)
like-new SK set (pawn shop)
multiple used Snap-On sets (Craigslist)
Craftsman Professional 13 piece sets, USA made
Craftsman Full Polish 13 piece sets, China made
Craftsman "Full Polish" 18 piece and 10 piece sets (identical wrenches to Craftsman Professional 13 piece, but different sizes)
Craftsman Cross-Force sets, ratcheting and non-ratcheting, USA made and China made
Craftsman locking flexible sets, USA made
Craftsman Professional 12-piece offset box end set
Gearwrench flexible sets, Taiwan made and China made
Gearwrench X-Beam
Harbor Freight Pittsburgh Pro V-groove
Harbor Freight Pittsburgh long handle
I found the USA made Craftsman Professional wrenches absolutely fantastic in terms of length, weight, feel, and finish. The individual wrenches in the 13-piece sets were identical to those in the 18-piece and 10-piece "module" sets called "full polish".
The SK wrenches were comparable in quality, but IMO no better, and over double the price with warranty replacement being difficult at best.
The (used) Snap-On wrenches had a nice length, weight and feel. Again IMO no better, but even in their extremely worn condition, over triple the price. And, not having the benefit of a Snap-On truck stopping by, no convenience/warranty benefit.
The China made Craftsman Full Polish were similar in length and weight, but the finish was sub-par, with pitting in the chrome and machining marks in the open ends of the wrenches, like on Cman raised panels.
USA made Craftsman Cross-Force wrenches had the same quality finish as the USA made Craftsman Professionals. The smaller sizes were longer in length than the Cman Pros, for more leverage. The quality of the USA-made Cross-Force reversible ratcheting wrenches was also very high. The larger size Cross-Force wrenches were significantly thicker and heavier than the Cman Pros, though, which I personally did not care for as much. Very nice wrenches, though.
The China made Cross-Force wrenches, like the China-made full polish wrenches, were significantly inferior to those made in the USA, with pitting all over the chrome, and rough machining in the open ends, like (cheaper) Cman raised panels.
The Gearwrench flexible sets surprised me, as I found the weight, feel, and finish quite nice in both the Taiwan and China sets. The ratcheting mechanism felt more positive and more consistent across wrenches in the Taiwan sets.
The USA made Craftsman locking flex wrenches were thicker, longer, and heavier than the Gearwrench sets, with a nice finish. Side note: They count on you buying both metric and standard, as the sizes that have close standard equivalents are missing from the metric set.
The Craftsman Professional 12-piece offset box end set is only available shipped, not in stores. USA-made, and have the same high quality fit, finish, and feel as the USA-made combination Cman Pro sets. Stores do sell the 5 piece sets.
The Gearwrench X-beam felt a bit cheap to me, and I did not care for the built-in nut detent that only allowed use from one side of the ratchet. The length and finish were nice, though.
The HF Pittsburgh Pro V-groove wrench set, available only in standard (no metric), has a great length, weight, and feel. These are nice, thick, strong wrenches. The finish is sub-par compared to anything USA-made, but better than the finish on most other HF sets. Some of the box end holes were a bit off center. For $22 on sale, though, this set is unbelievably nice.
The HF Pittsburgh long handle wrench set has a nice length, but felt very thin, light, and cheap compared to the other wrenches I looked at. The finish was wavy and horrible.
Sorry for the long post, but hopefully all of this information will help you avoid spending 50 to 100 hours going through the same process.