Popular as in how common this combination is used or how happy we are with the reliability of Eye Fi.
FWIW, I have experienced the shutter lockup with my 5Dm3 without Eye Fi, not yet had the problem wile using this card.
Re Eye Fi, one you get it set up, works great for onesies twosies shooting, if you're doing a lot of shots or time lapse, the wifi connection in direct mode always craps out after a number of shots and requires a card pull to get it working again.