Cesc has shown world class performances for years. He has repeatedly proven that he could score 15 - 20 plus assist around 20 goals in a season from midfield. His vision, movement, passing (range) and touch (albeit a bit heavier than Xaviesta's) is La Masia certified. Tactically he has been wasted in the Premier League and there was no way he could have fitted in into the complex Barcelona movement and pressing system in his very first season without looking out of place and tiring out in the second half of the season conditionally but it was only a matter of time until he would fit in perfectly and not look out of place.
Sanchez was more of a gamble. Firstly he only played 3 seasons in Europe before we bought him and he did it in the post Calciopoli era. Pretty much the lowest point in Italian football where a retard like Mancini was winning stuff. Not even remotely close to the vintage 90s Serie A. Secondly we looked for someone who was advertised as a superior dribbler who could unsettle defenses. And while he could provide that with Udinese where he had all the time and space in the world because no one parks the bus against a mid table team, he doesn't have that luxury in Barcelona anymore and his limitations in tight spaces become blatantly evident. He actually completed less dribbles than Busquets so far this season while in Serie A he had the most amount of successful dribbles in the whole league.
He gets shrugged of the ball extremely easily which doesn't surprise me with his stature. He got some abs but he's still a lightweight who's even smaller and infinitely weaker than Messi (who is actually built like Hulk). Apart from that his goalscoring has never been his main strength anyway (neither his goal creation). In Italy he scored 21 goals in 3 seasons (+ 11 assists) while playing centrally most of the time. Scoring 15 goals for us last season he punched above his weight tbh. First season syndrome I assume when the defenders in La Liga didn't know him yet. There are only 2 things he does well right now. Workrate and off-the ball movement and that's it really. But make no mistakes. Competent defenders in the CL knockout stages won't get dragged away like that Betis fullback did by a simple diagonal run. For a Barcelona forward that's not enough. If he doesn't beat his man, he needs to at least score. If he doesn't score, he needs to at least beat his marker and be a menace on the wings. If he doesn't do neither, I don't see what he offers that Cuenca or Tello can't offer (nevermind Villa) and how he was worth € 26 + € 11 million. Oh, yeah. And he is injury-prone. Which doesn't help his non-existent consistency either.
In short: Fabregas >>> Alexis. Passing, scoring, creating, keeping possession ... even dribbling, fsss. Here's hoping that he'll shut me up in the second half of the season. Sigh ...