My cougar experience:
The springs felt extremely stiff the first few times I ised it, but the softened up quite dramatically over the first 2 weeks of use. I think they are perfect now, and found it hard to go back to a normal joystick, which feels way to soft to me.
The first major problem I had with my stick was that after a couple of weeks of use, I noticed that there was a bit of "slop" around the centre point ... i.e. you could move the stick a few millimetres each way before the springs engaged. Over a few months this slop zone grew (as the metal components stretched I assume) until it became unbearable. In the end I was able to move the stick 1.5 centimeters before the springs engaged.
I eventually solved this problem when I found a guy here in Australia who modifies the mechanism with specially machined metal plates. I have now had about 2 months on the modified stick and it is still nice and tight. Unfortunately, the cost was half what I paid for the stick in the first place
Now I have a new problem, spiky pots. Every thrustmaster stick I have ever used has had crappy quality spiky pots, and the cougar is no different. I remember on the message boards before the stick came out thrustmaster representatives assured me over and over that spiking will never occur with the cougar. 2 weeks after I got my stick it was spiking badly. I went to the message boards and there were literally dozens of people complaining about the same thing.
Cleaning the pots manually seemed to help ... for a while. After about the 10th time I cleaned the pots out I gave up. I am now using a crappy old Microsoft sidewinder stick that I have had for 2 years that still works perfectly and never needs recalibrating.
I now have to decide whether to just ditch my $AUD750 stick (ouch) or fork out another $AUD250 to get hall sensor pots (ouch). If I do that I will have a stick that should last 10 years ... but ffs, for the ridiculous price the thing should have worked out of the box!
I have also owned CH gear in the past and it lasted years with no problems. My advice to you, stick to CH. The cougar is an awesome concept but definately not worth the money. If I had my time again I would have gone CH again.