My S4 was thicker than all of my Apple Watches but on wrist it was a non issue because of the round form factor. Round watches fell more comfortable on the wrist than square watches. Square watches are better at displaying more information especially during long runs. Heart rate cadence etc. So even if thicker, the round form factor will make up for how it feels on the wrist. Square watches to tend to appear more "chiunky" because they're square. There's always a trade off. BTW the watch that was found is still a prototype.