After some extensive test flying I noticed a few issues with this plane (P3Dv4):
no internal floodlights that actually work: so when it's dark outside the flight deck stays dark too. Only the buttons can be illuminated. Workaround: use time preview to find the switches to illuminate the buttons. Fixed, see below
no ILS: no matter what I tried, it would not give me a glideslope. As a workaround I'm using the "Visual Flight Path" option of P3D. Not too realistic, but at least this allows to land the thing in 0 visibility. As soon as I can see the runway I simply change the nav 1 frequency to get rid of the unrealistic flight path on screen.
systems not always turning on/off, even though the buttons/switches indicate they are on/off. So far this happened to the pitot heat and yaw damper. Sometimes it can be fixed by toggling the buttons, but on the last flight nose wheel steering did not came back no matter what I tried. The gear indicator also not always shows 3 green lights.
no warning sounds whatsoever. Just a master caution light. Probably a sound DLL that's not 64 bit compatible. Fixed, see below
When you can live with these workarounds it's a very nice plane. Especially in games like Air Hauler 2 or FS Economy. If you can't, then you'll be very disappointed even at only $12.