that one was a brand new X-56 I tried in a shop, it was already branded as a Logitech which I forgot bought Madcatz, the throttle barely moved and when I adjusted the tension spring it did nothing to help it move, my X-55 moves smoothly the way it was when I bought it, which means that the X-56 would be like that or worse after a couple of years.

I cleaned my X-55 on the outside as the rubber was a bit sticky with a kind of glue in some parts, my guess is that the coating is slowly coming off, but once clean it looks OK again.