I've Silverstone FM123 and used FM92 before as well. FM123 trumps the CM fan hand down. No doubt or argument bout it.

First, the FM123 has higher rated speed which can be adjusted as you wish with the adjustable contoller.
Second, the FM123 will boost higher CFM along with higher speed been adjusted.

In conclusion and from my personal experience. The CM fan does pushes air and you can actually feel the air flowing if you're using it as an exhaust fan. But if wanna compared to Dual-ball bearing, high quality build, adjustable speed FM123, the FM123 is one of the best fan with high CFM's that no doubt push a hell lot of air.