All the Gunners I know were pleased to get shot of Gael in the summer, saying his crossing and decision-making is woeful. They said he was decent defensively but all-too-often he would be the reason that promising moves down the left would break down.
I reserved my judgement but could definitely recall personally seeing that happen in some of their Champions League games over recent seasons so feared the worst.
However since his arrival he has been excellent. I think perhaps at Arsenal he was too sure of his starting place and would try the extravagent. Whereas with AK providing stiff competition Clichy has kept things neat and simple so far.
He's not tried to be the main man down the left and has instead provided a key support role for Silva and co. In that regard he has been superb.
Like others have said, for £7m he looks an absolute steal.