For someone who has been watching both players for way longer than their short careers in the Premier League, I can tell anyone who is willing to listen that Yaya has always been the better footballer. And I don't say this as a City fan. This has been my contention for 6 years. Since the 2004 African Nations Cup.
He is slighly older now and has gained some weight. But even now, you can still see that wierd dribble where he doesn't do anything but push the ball into the most uncomfortable area for the defender and keep it under deft control. And his vision is way better than Essien's. His ball control, touch pass and shooting ability are all way better.
He is and has always been a technically superior player to Essien. The only area where Essien is better is his defensive force and hustle. As much as people don't realize it, Yaya has never been a brut like Essien. Hell he did not play DM for anyone but Barca, hence why I used to always laff at the idea that he was a DM. The English press is so insular sometimes.
For Cote D'voire, Donesk, Olympiakos and Monaco he played as an AM or a box to box CM. The only stop in his career where he played predominantly as a DM was at Barca. I find myseld always trying to clarify the misconception that he was a DM. Apparently even his teammates tot he was :?
Besides playing DM at Barca is not really like playing DM anywhere else. Barca's DMs are often just extremely skilled midfielders who just aren't good enough to oust Xavi or Iniesta. Frankly I'd take Busquet over 95% of the CM's in the Premiership.
Anyway, I have always rated Yaya the better of the 2. Just always brought more to the table. Especially when you watch them play for their respective countries.