Took City a few years to get it right. They bought some serious amount of dross for big amounts (Benjani, Santa Cruz even Robinho to an extent) however they have a lot more money than us and were able to easily continue to pump out the cash for players. In one window they signed the right players though, 09/10 they brought in Gareth Barry, Kolo Toure, Tevez - then the following year David Silva, Dzeko, Milner and Yaya Toure. That season was the first time they finished in the top 4.
Allan could be one of those key players for us - he's the same age now as Barry was when he signed for City and he completely settled the midfield. Get him signed up.