I have (I guess had now, since I got the X Friday) a 6 (not 6S). iOS ran like crap on it. My daughter and wife both have 6S’s, and they both say 11 runs sluggish on them. I have a 7 for work, and it runs fine. The only variable I see is that my old 6, and the two 6S’s all have a bunch of shit on them compared to my…