In the last week I've hunted and found both shiny Poliwhirl and Sandshrew in friend safari. However, even though I used a syncer as my first pokemon, the ivs for both were too poor to even consider battling with.
Funnily enough these friend safari catches were literally a side project. I've been masuda methoding my a** off for well over 1k eggs(lost count probably way more) with the intention of hatching a shiny machop. I've been doing it so long that I now have 5 perfect IV Machops with both guts/no guard and being male/female. Friend safari is way way way quicker, but ive just been unlucky with ivs/nature etc.
I've used masuda twice before, once in platinum where it literally took the full 1400 eggs for a shiny charmander, great ivs and timid (nature wasn't guaranteed back then) and once in X and Y for a shiny pinsir which took me around the same amount of hatches.
Based on all the other posts I see from players getting theirs in the first 100 hatches I assumed that Machop maybe where I got lucky, sadly this hasn't been the case.