I come from a "strings schizofrenia" period, in which I couldn't decide what I liked most on my two sopranos.
First I tried the Super nylgut, and on my cheap laminate uke they didn't change much from the black nylon stock.
I then tried the New nylgut, and found them to be better on that uke. On the same uke I tried fluorocarbon and d'addario black nylon, but both were lacking in bass frequencies, so I came back to new nylgut.
On my Ohana sk38 I started with stock new nylgut, and I didn't liked them. I tried the Super nylgut, and fell in love, but soon tried the fluorocarbon from D'addario, which hit me right in the heart... for a couple of months...
They were bright, clear and with lot of sustain, but after a while I understood that from my sopranos I wanted short sustain and a fuller sound, not the crispy bright tone of fluorocarbon.
So I tried black nylon, but they were too mellow and low in volume (but wonderfully sounding), and went back to Super nylgut. Since then I found peace.
I love the mellow sound and short sustain, over the bright and modern fluorocarbon (which reminds me the steel string guitar...), and the overall sound is fuller and richer.
Also, I really like the gauge in the super nylgut set, it has the perfect balance in tension.