I actually just dusted off an old reel of Forten Nylon 16 ga. in spiffy yellow to try in my newer Volkl V-Sense 10 325g's and it's working nicely so far. Better than what I remember when I initially tried this string - I think it's playing semi-soft in the summer heat. Affordable string, but I've never seen it in 17 ga.
My all-time favorite syn. gut is Tecnifibre. I just grabbed the last six individual sets that TW had in 16 ga. - I found those by accident when I was looking at other syn. guts and these were suggested at the bottom of the page when I looked at sets of Volkl Classic SG. TW stopped carrying this stuff a couple years ago, so I switched to Kirschbaum... that's gone, too. I'm feeling like the Grim Reaper of syn. gut!!
Happy to report that I think I've found more Tecnifibre SG from another source. While the Kirschbaum SG was nicely affordable at $35/reel, I absolutely do NOT mind paying an extra $20 for a reel of the Tecnifibre string. I remember it as playing slightly more soft than Prince Original SG, while Gosen OGSM has played another step up in the firmness scale. With Gosen and Tecnifibre syn. guts on hand, I should have a great many of my bases covered.
The Gosen is probably the winner in terms of durability and it's likely more firm and crisp feeling, but I wouldn't call it "harsh". It's been great for me as a cross when I string poly hybrids for locals I know. The Prince Original is sort of a Goldilocks syn. gut - right down the middle of the spectrum in terms of firmness and decent durability. Still a winner, but I never see it in reels. The Tecnifibre SG is plush, wonderful string with average durability - certainly better service life for me than ultra-soft Forten Sweet.