Fair enough, thank you Kyle for your comprehensive and well reasoned response.
There are undoubtedly issues on both sides, P3D is criticised for it's poor UI, flat runways and 'on-rails' air physics, while XP has poor ground physics, thread restrictions and limited developer API.
I'm still curious to know what is preventing further active XP development from PMDG however. Is it an issue of resource, API restrictions or perceived limited market share?
The trend indicated by the Navigraph survey is certainly interesting and I'd very much hope to see a PMDG liner for XP within the next couple of years, which I (and I'm sure many others) would readily purchase.
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