I used the stock cooler for one day and decided better not to live with it. So I picked up Scythe Mugen 2. and I am very happy with it ever since. The CPU is more than 10 degree cooler comparing to stock cooler. Scythe Mugen 2 with 100% fan speed is even much more silent than stock cooler with silent fan profile at idle.
Just as the other post mentioned, you do need 2 pair of hands to install SM2, one pair hold the cooler and the other one put on screws on the other side of motherboard. And make sure it can fit you case