Savarez 520 F
I placed these strings on two guitars, Flamenco and a crossover nylon. They are good strings, I like the fact of the wound G and thin caliper of the strings. They are very high tension and on the crossover, the sound is very punchy and a little nasal.
On the Flamenco guitar it works well, tight and bright.
Something about these strings that I have a concern is the windings are not very durable, they peal off within 10 hours of play. I have not snapped a string but when you slide your fingers over them, they show indentations where they touch the frets.
Also, after some playing, Some strings will have a slight buzz / bussing harmonics at certain frequesncies, sounds like it's coming from the saddle / bridge area - like the wound strings are coming apart and create a sitar like sound.
Note that both my guitars are professionally set up and are of sound quality.
Overall, like their gauge and snap when new.
The bad, does not last as long as other nylon strings.