I put a set of extreme bowstrings and am impressed with them so far but any smaller custom string builder will pay attention to the details and let you pick the string material they offer.
I got mine from Lance at Ledbetter Archery. He runs a shop in Texas. Shipped my strings to Idaho after several conversation on what my bow specs were and what I wanted. Great guy and super detailed. Strung up some awesome strings.
I would be concerned more about the string material than who is making them. There are only so many ways to make a string and most do that. There is a thread from about a month ago about string / cable material and there may be information in there that may help. I would recommend any reputable company if they offer the string material that suits your needs.
Ive haf amazomg lick with Threadz Custom Bpwstromgs. Its a small business with amazing customer service. Strimgs usually ship withimg a dau of ordering evem with custom colors.$100 for a full set.
America’s Best Bowstrings is what my shop sells so I went with the platinum line, no complains, no peep rotation, got a couple more FPS out of the bow from stock too.
Lookingbat tournament archery and knowing those guys can shoot whatever they want i see a lot of 60x abb and threadz and can say i have had great luck with all 3 but now its 60x or threadz for me both have been good abb just arnt any better in my eyes for the extra money.