I have seen that AF-C pulsing effect on most lenses that i own, specially at smaller apertures (f8 and up). I have also read about it quite a bit. It seems to be "normal" on the A7R2 and is one of that camera's limitations as far as AF goes.
The A9 (and I assume, the a6500) should be free of such issues.
Everyone agrees that AF-S works perfectly.
Thanks for verifying the AF-C issues with the a7rII. Once I get my other camera back, I"ll test and see how it works on it.
Oh, tomorrow is supposed to drop to a balmy 94° with a chance of rain so there may be an awesome sunset in the making.