When locked onto a CPU the device is secure, at no time during normal operation did the mounted heatsink pop off of the processor.
Part of the allure of Net-N-Dude to both professional and amateur CPU overclockers alike is the fact that they sell CPU/cooler combos that they "guarantee" to be able to run at a certain MHz level.
Thanks to the Glacier 4500 P3 Net-N-Dude is now selling P3-450 CPUs that have been tested with the cooler that can operate at a mind-bending 675MHz (4.5 x 150MHz).
Sharp readers are already surmising that this makes using the 675MHz kit somewhat of a problem thanks to its AGP-frying 100MHz bus speed (2/3 of 150MHz = 100MHz AGP speed).
Luckily there are mainboards utilizing core logic sets produced by VIA that can operate the AGP bus on a 1/2 clock divider instead of the 440BX's 2/3 clock divider, which would offer compatibility for your video accelerator even when using a CPU that runs on a 150MHz bus.
It's amazing to us that a P3-450 CPU can even attain such a high level of speed without active cooling (the utilization of active refrigeration to lower temperatures) and Net-N-Dude assures us that they have a full money back policy should a user not be satisfied with the kit for any reason.