I've been poking around in my guild's raid logs since the patch, partly because I'm so glad to be rid of Sidewinders, and partly because being rid of Sidewinders didn't make me worse.
Pre-7.1.5: ilvl 870, average DPS for boss fights in heroic Emerald Nightmare: 209,635.1 (log)
Post-7.1.5: ilvl 876, average DPS for boss fights in heroic Emerald Nightmare: 240,105.2 (log)
My ilvl has only gone up a little, but that's about the same kind of boost in raw numbers that I saw from initially switching to Sidewinders a few weeks into normal Emerald Nightmare. I didn't like doing it; I like the on-demand instant shot that Arcane Shot has become, and other than kind of switching Marked Shot for Serpent Sting, it's the same three shots that were the core of my Molten Core rotation.
I realize a lot of hunters are disappointed in Marksman (and Beast Mastery) right now, but playing at the level I am (where that 308k on Nythendra is kind of a personal non-trash best), I'm really happy with my numbers. I'm also really happy to have some traps back.
After this long, I had gotten used to the Sidewinders/Marked Shot AOE, but by the time we got to Dragons trash I was pushing out relatively decent numbers again.
Overall, across our raid group, the patch was good. We steamrolled through H-Emerald Nightmare, beating our record times for both Cenarius and Xavius, andwent for a couple easy kills in normal Trial of Valor, but no one wanted to go through then minutes of Helya after all that. Sunday we're going to look at heroic Trial of Valor and see what it looks like now.
Still want some kind of really AOE (either damage or heals) for my discipline priest, but that doesn't seem likely at this point.