I'm certain this has been said before, but I want to cast my vote for Aquila's Ambra 2000 string set. I believe the entire set is medium tension. The trebles are Nylgut and the basses are wound Nygut mono-filament. As others have said, they take a while to settle in, both in stretch and tone. The bass strings are unlike any string I have played before. They begin with a dull tone(I'm accustomed to base strings sounding great at first and then becoming dull very quickly), but become much cleaner and sweeter in a day or so. Sustain and volume are both good, probably not the best for the concert hall, but a pure tone that accentuates the fundamental. Perfect for home and recital hall. That is very nice to my ears and matches my playing well. The trebles are clean and crisp. They are bright without sounding metallic and maintain their sweet sound. And.... the trebles seem to last forever. I'm on my third set now and I've never had a treble string become dull. In fact I only change them when I change the basses so I don't have a stash of trebles sitting on my desk.
Then there is the cost. I don't know why they are so inexpensive, but they are.
For those who may be interested, I play an Esteve 3z. Strings and guitar are a good match.
I will probably never be able to justify the cost of gut strings. Aquila Ambra 2000s are intended to approximate the sound of genuine gut strings. So I can't tell you how similar the 2000s are to real thing, but I like the sweet clear sound, and I like the price. What more can I ask for?