I’m a regular Skratch user for years now. Love it. I tried Tailwind for the first time about two weeks ago, and I really liked it, too. I found Tailwind to be a good bit sweeter than Skratch, not surprising looking at the calorie count, but not Gatorade-sickly-sweet. The Tailwind is also a lot saltier in taste, which I think also shows up on the nutrition label, though I don’t recall the numbers.
There’s a place for both. I like Skratch (and Osmo) for long, hot days when I need a lot of hydration but not necessarily all the calories that come with drinking a higher-calorie drink. You could alternate with Tailwind to get calories in, or go Tailwind-only in colder weather when you don’t need as much fluid per hour.