They're awesome, as you've likely heard a thousand times before. Figured you needed to hear it at least one more time though.
i've tried playing with those and i dont like them at all, but i can see how it would give you more precise movements so you can play on higher turn speed. I am unlike most people and tend to play on either 1, 2, and somtimes 3 that way there is less of a chance i will miss the headshot.
With the fps kontrol freeks you are able to play on a higher sensitivity and it's like playing on a lower one. i play (cod) on 10 sensitivity and feel like its maybe a 6 or 7 if i would take them off.
my sensitivity is set to 10 and they feel awesome!!!!!!! lulz
I use them and I love 'em!