Ranking aircraft manufacturers by after sales support

how do aircraft manufacturers rank in terms of after sales support? (politics aside)

high tier:
Saab (lots of good feedback from european operators)
Lockmart
Boink
Mil

mid tier:
Dassault (would move this higher but it seems their tendency to gauge customers after sales makes many reluctant to consider it at times)
IAPO (India had a few problems but it eventually got resolved)

garbage tier:
MiG/Kimov (lots of complaints and unservicability , but not sure if this is because of rosobonexport or because much of this was in the 90s)
Hongdu (lots of poor quality spares)