I have TM hotas cougar and I'm looking to buy the playseat flight.
Does the seat provide any sort of mounting method to hold the stick and the throttle firmly?
I wonder because if it's just putting them on the side plates of the seat, then I don't think the stick won't stay put while flying.
Anyone have any experience ?

I think there are screw holes to secure your gear to the plates... if not, it'll be easy enough to drill them. Others I've seen have used velcro straps to hold the joystick/throttle in place.

The Cougar base is very heavy. So much that it does not even have suction cups, just relies on rubber feets to stay put on a desk. I think that velcro straps would be plenty sufficient to hold everything in place, until you decide to replace the whole of the Cougar base for a DIY version

One easy nice fix would be to remove the Cougar bottom plate. Drill holes on the playseat side plate and fasten the cougar on to it using the sideplate as the cougars new bottom plate. A semi-permanent solution. But you can allways remove the cougar and return it to it's bottom plate, and 4 little holes on the playseat sideplate aren't really going to be that bad.

Very good idea. And you can use the cougar's bottom plate as a template for marking and drilling the holes.

What playseat model do you have? There are different options available depending on what version of the seat you have. Newer models have side mount options available, older ones like mine require you to make your own mounts. I over engineered mine by separating the seat from the base and placing a 1/2" hardwood deck in between. I then bolted a 2x4 onto the deck and cut it to stick out just past the seat so I could mount a threaded floor flange for pipe. The rest is more easily explained by pictures:

http://simhq.com/forum/ubbthreads.php/topics/2712940/Re_A_Good_Joystick_to_Hack.html#Post2712940

Scroll down to see the mount. In any case probably not what you're looking for but it can be done.

Not a Playseat, a Gameracer. But very similar design.
I hacve it paired up with a Bob Earl Monitor stand




I used to have a DIY wooden affair with a Car race seat. But elected to go with the Gameracer because of the nice design and the Mrs doesn't object.

Just waiting on a Metal'n'wood extension for my Warthog now and it'll be complete