More CH, Thrustmaster
We're less enamored with the CH Pro Throttle. It's definitely got more buttons and thus more programming options than the X52's throttle, and would probably be a better choice for complicated jet sims where there's much more of a need for multiple buttons. However, in World War II or World War I sims, we do prefer the X52 throttle for several reasons. For starters, it's a tilting throttle, rather than a sliding one. The adjustable tightness on the X52 doesn't affect performance but it does affect feel. Ultimately, however, what sold us on the X52 throttle is the trim wheels. Whether you're playing IL-2, WarBirds, Aces High or World War II Online, you know that trimming an aircraft to fly straight and level is a chore. While it's certainly possible to do this with key presses, it works much better when there are two spare axises (axes? axii? hmm... dictionary.com says axes, let's go with that) that can be used to adjust rudder, aileron and/or elevator trim settings.
CH's best feature, a definite killer app, is the CH Control Manager Software. It's not quite as flashy, simple or intuitive as Saitek's programming goodies, but it is more reliable and robust. In certain games we'd have problems with macros on the X52, no matter what we tried - but these issues did not appear with Control Manager. In addition to basic programming, such as assigning key presses and macros to buttons, the Control Manager item has one last definitive feature. Many older and even some newer games are incapable of identifying separate input devices. The CH Control Manager permits the user to create a single virtual stick, that Windows and all games using DirectX input see as a single stick, out of multiple items. If, for example, the player had a CombatStick, a Pro Throttle and Pro Pedals, those would normally be three different items that needed to be programmed into a game. With Control Manager, it's possible to combine all three together, so that they're seen as a single item with multiple axes.
Thrustmaster
In terms of hardcore appeal, about the only item that could rival CH Products is the Thrustmaster Cougar. Though we tried to obtain one for comparison, we were unable to. However, after some research on various flight sim forums, as well as Cougar World, it seems that the consensus on the Thrustmaster Cougar is that it's a quality stick with decidedly shoddy components. The potentiometers, speedbrake, and other items are often in need of fixing or replacement (as the case may be).
A robust mod community has sprung up around the Cougar to alleviate or fix these issues. In fact, after many of the mods, the Cougar becomes better than new - more accurate, with less center play and less noticeable axis changes. Unlike CH, the Cougar's throttle is based off the actual F-16 design as well and does offer trim wheels. Of course, all this is true only if the owner wants to spend the extra change on new sensors and upgrades, or if he's willing to take the chance that his stick will not be one of the relatively many that are affected by quality issues. Finally, we should keep in mind that this is the rivet counting community - their perceptions of what is and is not acceptable in a joystick are much stricter, and they do put their sticks through more abuse. Of course, this is true of most CH owners as well. Incidentally, also being based on the F-16 stick, the Cougar likely suffers from the same super-sized hands issue.