if planning to overclock the CPU, then you'll need to make sure the air cooler is of sufficient quality.
I don't know what HSF is so I can't say what the cooling capabilities are for it.
The AiO from ID Cooling should be decent enough though. You're not gonna break records with it, but should provide enough cooling power to allow you to get maybe a little more than 4.0Ghz on he CPU (like maybe 4.2Ghz.)
I assume there's fans at the front of the case as well already and a single fan at the rear?
gotta have proper air flow, especially if mounting to the top, since when you mount to the top all the hot air inside the case is going right into that radiator, making it's ability to cool the liquid in the radiator lesser that it would be mounted to the front of the case (assuming the case supports front mounted rads.)
What PC case do you have?
And if it's possible to have a 240 or 280mm rad mounted to the front instead, then that would offer better cooling than mounting it to the top.
otherwise, if top mounted is your only option, then that's what you have to deal with, and you just have to make sure that you have good proper front intake for getting as much cool air to flow into and through the case as possible.