Most mounting systems tend to be secure but with the Megahalem I found that when you try to place that center bracket, you have to make sure the cooler does not move and that it stays aligned with the side brackets. In the end I always ended up moving the cooler causing the thermal paste to spread unevenly.
I test a lot of coolers and the Thermolab Baram was very good to work with, so much so that it's one of the only coolers I have kept. The original mounting kit was horrendous but they improved on it vastly!
Don't get me wrong, the Megahalem is still an excellent cooler but the Thermolab is cheaper and comes with 2 sets of wire clips for a 2 fan configuration.