I skipped Snap-on entirely, because I dislike laser etching, they are way too expensive for the amount I will use them, the box end chamfering is too deep for my liking on the smaller sizes, and they don't make one of the sizes I needed.
Instead, I first tried out the Sunex (Taiwan) metric set because it seemed to have good reviews from others on GJ, and I found one for a great price online. I ended up selling it off because the chamfering on the smaller sizes was terrible. The box ends were chamfered so deeply, there was almost no 12pt engagement on a fastener head. I then tried out NAPA's Carlyle (Taiwan) adapters. They are more expensive than Sunex, but Carlyle allowed me to buy the individual adapters I needed instead of forcing me to buy a whole set so the overall price I paid ended up about the same as Sunex. They were a bit better in terms of the chamfering, but I wouldn't call them good either. Two of the 4 I bought also had the box end broaches obviously off-center to the point where they were quite thin on one side. I wasn't impressed, so I got rid of those too. This sort of dynamic is one of the pitfalls of ordering online and not being able to see something in person before making a purchase.
I ended up trying Capri (Taiwan) next, and I've been happy with them. Centered broaching, acceptable levels of chamfering on their small and large sizes, etc. 3/8" drive sizes are $15 each if you don't want a full set. I bought a couple sizes in 3/8" drive and two in 1/2" drive as well ($20 each). Capri is one of the only brands that makes SAE and metric torque adapters in 1/2" drive. Capri also has the brand and size stamped on the adapter instead of it all being laser engraved like some other brands do. That's partly why I went with them instead of a brand like Firstinfo, Boxo, etc. that has laser etched branding, could be gone tomorrow, and only sells full sets. Capri also has a brand reputation to worry about. The lesser brands you often only see on Amazon will just disappear or change their name to something else if the ratings for their products get too bad. My thought was that Capri is slowly growing as a brand. As far as I can tell, everything they sell is made in Taiwan. Their website is well designed and informative, and their products overall also have good ratings, unlike a larger company like Sunex that is a more well-known brand but has always had a garbage website and they put out a mix of poorly made tools and good tools made in various countries.
Most of the desired dimensions are available on the Capri website if you scroll all the way down to the bottom of each page.
3/8dr metric-
https://capritools.com/shop/3-8-drive-torque-adapter-metric/
3/8dr SAE-
https://capritools.com/shop/3-8-drive-torque-adapter-sae/
1/2dr metric-
https://capritools.com/shop/1-2-drive-torque-adapter-metric/
12dr SAE-
https://capritools.com/shop/1-2-drive-torque-adapter-sae/
In terms of strength, it would be nice if someone like Project Farm did some comparison testing of a bunch of brands to see how they compare. My Capri torque adapters have worked for what I needed them for so far, but I'm not sure how far I can push them without breaking them either. Every brand I looked into before making my purchases had online stories of happy customers and also breakage. Pretty much every brand out there also has one or more obvious design deficiencies that could lead to breakage under moderate to high levels of torque. Capri and several other brands, put the ball detent or pin lock hole in a potentially bad location on the square drive end creating a weak point. Snap-on and several other brands, don't stress relieve the corners on the square drive end on their torque adapters at all. Sunex and multiple other brands, have way too much box end chamfer on the smaller sizes. Any one of those things can lead to adapter breakage or fastener stripping when using higher torque levels. That's why it's nice to have redundancy and options when using tools designed for working in tight areas.
