Pro variant has colorful LED buttons (RGB). They can be controlled via native Logitech/Saitek software. There might be some small differences in the internals, but for 95% it is purely esthetics. I actually managed to control the LED color state via small scripting (C++), which might give more fun in simulations.
Unfortunately, this is not directly due to Galaxus, but to the supplier. But be patient... it will come soon. I ordered mine at the beginning of October and it arrived in mid-January...
Unfortunately, we currently have no information on when the item will be available and when we will be able to deliver it. As soon as something changes in this regard, we will post it here. Sorry.