Fremont Blackline Mediums... I can't stand nylon strings, I'd take fluorocarbon any day of the week. The humidity level in Taiwan often hovers around 90% and causes nylon strings to constantly go out of tune. I had a set of Aquilas on one of my old mahogany sopranos and had an issue with both intonation and tuning, but after swithing them out I found that my problem wasn't really with the friction pegs but the strings... the intonation was also fixed with the string change. Given a stable climate and a cheap soprano however, I would consider Aquilas to be a good choice since they improve the volume and tone. Whenever I buy a new ukulele that's strung up with Aquilas, I have to buy new fluorocarbon strings with it to change them immediately... it's a bit of a hassle.