It works fine for me.
I'm using the AV8B without issues. The only thing needed to make it work is to add the dlls inside the DLL.xml file, because the FSX installer is not able to do that properly.
<Launch.Addon>
<Name>RAZBAM AV-8B Harrier Control Manager</Name>
<Disabled>False</Disabled>
<ManualLoad>False</ManualLoad>
<Path>G:\Prepar3D v3\Addon Modules\RZAV8BCM.dll</Path>
<DllStartName>module_init</DllStartName>
<DllStopName>module_deinit</DllStopName>
</Launch.Addon>