I'm no expert but I agree that Syk is not the quality of real silk line, but it's high point is no maintenance, it needs dressing with a bit of mucillin though. You do have to cut and tune it to suit your casting style like most lines. I have a couple of silk lines that I fish occasionally. Grew up fishing silk when I was a lad, the routine was to fish the morning then unreel the line on the bushes to dry for the afternoon hatch. You could also flip it end for end and fish again but silk does start to sink after a while, and needs another application of Red Mucillin after it is dry to bring it back to it's former glory. I don't always want to deal with the maintenance of a Silk line every trip thus I like Sylk. Mind you I have a line that was bought in the 20's by my Dad that is still great to fish. No modern line could boast that or even fish like it.
By far the two best silk lines I've tried, where the a Phoenix Silk Line and JB Thebault's lines, both suburb. Both American built and extremely nice. All new silk lines of course require some breaking in to remove the initial stiffness before fishing them. They are not cheap but properly cared for last a lifetime. I have a Chinese silk line on order and will report on that one once it arrives and I put it through it's paces over a couple of months. Not everyone wants to deal with the maintenance and care that go with these lines, they can mildew and be destroyed by moisture if not properly cared for, but the performance is certainly second to none.