Apparently their service hasn't improved in the years after this thread was started. Not a bit.
3 days ago I bought their new Pilatus PC-24 biz jet via Simmarket, downloaded and installed it. After i opened FSX Acceleration, the plane doesn't show how it should. In the preview pane it shows like some vague contours and on the runway I can only see a black plane. Cockpit is just a black page.
I opened a ticket on Saturday. we are now Monday afternoon 16:53 Melbourne time where IRIS is located and I haven't even gotten any response from them.
Needless to say that I'm more than disappointed.