I got them for the A-10C and now use them for just about every fixed wing aircraft (I have the Ka-50 but haven’t programed the MFDs for it yet as I am still befuddled just trying to fly from WP1 to WP2) - the Viggen (no @Troll, I do not have Eject mapped), even the Mig-21.
A couple of things to consider, to get the most out of them.
The A-10C is fairy strait forward - two MFDs in the cockpit = two physical MFDs. That said, the FSKs switch around as you switch screens. @Kinger is correct in saying that placement is important. Ideally, you should be looking at your screen while pressing the buttons. I place the two Cougar MFDs about where they would be in the cockpit - Right and Left with a separation between the two. Then it is just a quick downward glance (moving your eyes only) to see that you are pressing the right button. After a while it becomes second nature and it feels like you are really pressing the buttons on the screen.
The FA-18 has 3 MFDs so I’ve mapped the right hand Cougar to be the bottom MFD with the use of an additional Keyboard entry as a “Modifer” - I think I use the Shift Key…(I’d tell you but it appears that my FA-18 sim profile has been erased …deep breaths.
For jets without a MFD, it is actually a bit easier to use since there are n changing screens. I use both Cougar MFDs for bottoms/switches on the L and R cockpit panels. For example, in the Viggen, all the CK37 controls, Data panel and Navigation (B1, B2, etc.) are all on the right MFD in a logical sequence. The Radio buttons and a couple of the functions on the Left panel are mapped to the Left MFD, again, in a logical manner per the cockpit. So my left, top MFD button is the radio H button, the next to the right is the radios’s 1 button, etc.