I have had three go-rounds with the Clifton.
The first: the original Clifton. I liked it a lot, but found the thin tongue lacking. Also, I didn't feel like the upper offered enough support.
The second: a pair of black and white (Black/Anthracite) outsole Clifton 2 s. I bought them as soon as they came out. An improvement in the tongue, but not a comfortable fit in the upper. They were also a little too cushioned compared to the more firm ride of the original. An worryingly, the upper plastic
The third: another pair of Clifton 2 s. This time, the grey and yellow outsole (Grey/Acid). My reaction is that over the year, Hoka has tweaked the shoe to make it closer to the original. It has a better tongue, a nice forefoot fit, and a slightly firmer outsole than my first black 2. Still not perfect: the tongue doesn't stay put, sliding a little to the side when you run. But all in all, a solid shoe that works well on road and non- rooty, rocky or slippery dirt. A nice counterpart to the Challenger ATR 2.
Looking forward to the Clifton 3 at the end of Q2. It looks like I'll have worn these out by then - 26 miles and looking good.
Edit: Ooops! No sooner than I posted, I spotted overlay separating from the shoe just like in the first pair of 2 s I bought. Guess Hoka didn't solve this issue.