The Intel 'stock HSF' isn't what it used to be!
In the old days (pre-C2D) boxed fans would wind up like a Dremel tool, and sounded like a buzz-saw. These days, they run at a MUCH lower RPM, for the sake of peace and quiet. As you probably know, there's no such thing as a free lunch. Intel has given up performance for less noise, with their new HSFs.
So, the answer is... if you want something that's quiet, but only works so-so, the 'stock HSF' is probably better. However, if you're looking for enhanced cooling, and to hell with noise, the XP-90 is far better, as Operandi said.
