I bought a epix2 and index s2 in store, the epix pair fine with 1 less than a minutes, but the index s2 got me and the employee from Garmin official store crazy...
We were spending 1 hour on pairing and it keep show pairing failure, we thought the first one was broke, we opened a second one and they are the same.
We tryied two iphone, mine and the sales man, even he called another store, they can not pair it as well !!!
Come on Garmin, I have purchased MARQ, Epix2, Edge 1030, Vector 3, Approach R10 and Fenix, they all work really well expect of the vector 3 (thats another story, battery sucks everyone knos).
I end up bring a complete useless index S2 back and will try a week, if not that return it back.