I think that ORBX True Earth is the perfect add for XP 11 because that where XP really shines. But, that's the only difference I see from years ago. It's still the same sim with awful sounds and the weather is getting better with an expensive add-on, but it's just not at the level of P3D v4.5
I do love XP's terrain engine, roads and traffic movement, and the dusk & night lighting are second to none. But it's missing too many important features that are not even available as add-ons. The main issues are inherent within XP and they can only be addressed by the main developer.
Sorry for my rant, but I have respect for Jack & John and value their opinion. I was just hoping that my initial XP investment was not a waste of money. It looks like it still is.