I think Opto can be -1/2 to -1/1...I've thrown Goldline that are much less stable though (never tried a fresh one). I have weird results with my River, that I've thrown for a couple years. I think it has a strange design that makes it always want to fade/have LSS, while it initially is high speed understable. It has an interesting flight where if you can throw it cleanly with at least, I don't know...280+ power...it will have a mild turn and mild fade. But throw it harder...still mild turn and mild fade. And harder...and still mild turn and mild fade. Most US discs will gradually turn more and more, getting wider and wider S-curves at longer distances, and stop fading at a certain point. The River just always has this mellow LSS that fights the understability that makes it glide along I guess.
I normally don't get all analytical about molds, but this one is strange. I've thrown it 375'+ (very occasionally) with barely more lateral movement than a 320' shot with it. Normally a disc with a comparable flight path at 320' would flip like crazy at 375'. But, it rarely comes out for me on the course because it's finicky...if you expect it to do that, and you have any torque or weirdness, it can flip. But if you throw it correctly in calm or tailwind you are rewarded with glide.