I own 3 different code readers. There are differences - primarily in the coverage for different models. For a 955/957 Cayenne and a 987 Boxster I would STRONGLY suggest the FOXWELL NT530 with the Porsche software module. It covers all the systems in both cars and does programming for both cars. It enables replacing modules by reading the old module then downloading the information to the new module. Overall - it's the best I've seen for this. It doesn't quite have those capabilities for the 958 Cayenne. About $160 with the Porsche software.
I also own a Durametric Enthusiast - that's the last tool to be dragged out. Having to hookup a laptop to it and wait until everything connects correctly is frustrating, as is the lack of firmware updates from Durametric for about forever.
I also have an iCarScan X431. It comes in 2nd to the Foxwell. I believe both are based on the Launch reverse engineering of the PIWIS system as menus and capabilities are similar. The iCarScan X431 uses a Bluetooth OBD-II dongle and your cell phone to connect and read the data. It doesn't offer much in the way of programming for any vehicle I've tried it on, but I haven't paid for the latest Porsche update so there may be more capabilities now.
Question: I have a 2006 955 and the climate control flaps are clapping on startup for a few minutes. Do you know if Foxwell NT530 scanner can reset the flaps?
If you go to Foxwell's website, there is a spreadsheet that tells you what it will do for each model it covers. That can be found at:
https://www.foxwelltool.com/ext/support-fun-list.html - look for the menu selection "Function List" up near the top of the page.
Here is what it says on "Air Conditioning":
Active test should do it for you. And if it's like the iCarScan - the "Calibration" teaches the system which stepper motor (actuator) is which by running each one.