Strings... what are your favorite brands and sizes?
Preface: In the context of solid body electric guitars:
I am a big fan of Stingjoy for multiple reasons.
1. They sound good, and they are good quality.
2. You can order custom sets in terms of gauges. This is HUGE for people who play in non-standard tunings or atypical scale length guitars. I know I went 15+ years as a guitarist not understanding the relationship between string gauge, tuning, scale length, string tension, and tone. Stringjoy has a string tension calculator in their website that can help you determine the appropriate gauges for your specific setup. I made custom sets for my 6-string 25.5" scale drop-C guitar and my 7-string 25.5" drop-G# guitar, and actually using the appropriate gauges for those configurations makes all the difference in the world imo. The curated sets of gauges that string manufacturers prop up as an industry standards are fantastic for most cases, but having the option to create custom sets is a godsend for the rest of the guitarists.
3. They are made in Nashville. That's my hometown, and I always love supporting TN businesses.
4. I personally think their original "Balanced" tension sets are better than the industry standards. In a nutshell, these sets are their best determinations of standardized gauges that involve beefing up the low-E and B string. For example, their Balanced set is 10-48 instead of 10-46. Imo their logic for making those adjustments to those strings checks out, as evidenced by my experience (jmo).
5. They sell other useful items and have a cool rewards program. I am a fan of their plectrums and string cleaning items.
All that said, I used to swear by Ernie Ball green pack Reg Slink 10-46. Later, I got turned onto D'Addario NYXL, and tbh, I still LOVE those strings. They are articulate and clear; I fully admit they have extra air and zing that sounds fantastic compared to Stringjoy.