I really like World War I planes and wanted to buy one on the marketplace because that's where I have the funds. But while searching for videos and liveries, I came across an add-on for your plane that changes the flight model and some engine parameters. The description suggests it's closer to the actual performance of the original plane.

I can't post the link here on the forum, so search:
flightsim_to captain-sim-spad-xiii-update

I don't know if the marketplace and your plane files are encrypted, so that won't work.

So I'd have to buy it on another site or on simMarket, but that would require a PayPal payment, which is problematic for me.

Best regards