I have not purchased a Navigraph subscription yet. I am considering it for the new year, but so far I have had enough in finding up-to-date charts by googling "[ICAO] charts", or "[ICAO] AIP".
Not sure about FSX, because I fly MSFS2020 almost exclusively these days. But I ran into a nav data issue nevertheless the other day. Flying to Bata (FGBT) in Equatorial Guinea, My PMDG 737-800 had everything needed in the nav database, but the entire airport did not exist in MSFS2020
There was one tile the had the Bing maps image of the threshold of the runway, but the remainder was default tiles with grass and trees. As far as nav data goes, there was ony the BT VOR. But my 737 would let me program in the ILS approach nevertheless. Difficult when approaching minimums and not even the VOR has captured, let alone the GS
The real challenge was the next flight getting out of there. As the airport does not exist in MSFS2020, I could only set a GPS point as a User point of departure, but with a 737, that will put you up 31000 ft in the air. In a cold and dark state... That will overstress the airframe before you regain control. So Ihad to find naother airport nearby, fly to that non existant airpot, and start my flight from there.
Now, Navigraph would not have solved that issue completely, but it would have put the ILS into the sim (LOC and GS), making thisgs a touch easier.
But then again, that was the only issue I have had so far, and I get by fine with the free SimBrief without Navigraph subscription.
The argument that with a subscription you have the charts available "in sim" through the tablet is of no extra value for me, because I always have a browser open on my second screen anyway, and that will display the charts even bigger.
So I am still on considering a subscription, purely for the up to date nav data and easier to find (always in the same place) charts. But I consider it a luxury, rather than a necessity.
