I moved my MFD AP from my Bix 2 to my Phantom FX-61 and with almost zero tweaking ( I just loaded the X5 settings and changed my pack to 4S) my FX-61 flew like it was on rails when on STB and ALT* modes even with 12 - 15 km crosswinds. I have used other APs in the past and most of them require a bit of tweaking to get the plane dialed in.

https://youtu.be/5dlk9v0Av6E