Yes, Sharkskins shoot noticeably better. For lighter weight lines and shorter casts, where shooting line isn't a priority, the Sharkskin also: has no memory, lands very softly, mends easier, roll casts easier, and, if the company claims are even close to accurate, they'll outlast the next best lines by at least three times. The first four characteristics make these lines worth it to me. Shooting better is a nice to have extra, and longer life makes financial sense. Now, if they don't last longer, SA will be hearing from me and a lot of other anglers. I understand those who don't want to pay $100 for a fly line. I don't want to pay $70 for a premium fly line when $30 more will buy me a Sharkskin. Now, if we're comparing Sharkskins to discontinued premium lines like Rio Selective Trout II, available at a significant discount, the math tends to favor the discounted line. I haven't seen Sharkskins discounted (other than guide discounts and store employee discounts), so $40 or even $60 for one doesn't sound like a deal most of us can get.
-CC