My experience:
SU4: No CTDs
SU5: few CTDs, I would say 30% of the time
SU5 Hotfix 1: no more CTDs
SU5 Hotfix 2: So far CTD or Frozen computer 7 out 8 attempts
My 8 attempts to use MSFS SU5 Hotfix 2
Attempt #1: computer frozen, had to do a hard reset. No Mods.
Attempt #2: computer frozen, had to do a hard reset. No Mods.
Attempt #3: deleted UsrCfg and content.xml. No Mods.
Game started. Flight started on Autopilot. (vanilla Icon A5)
CTD one minute after takeoff.
Attempt #4: One Mod: Icon A5 improved, updated for SU5.
Game started. Flight started. Take off.
Flew over a nearby PG city.
CTD after a few minutes.
Attempt #5: No Mods.
CTD in the World Map when zooming to select an airport. Never happened before.
Attempt #6: No Mods.
CTD in the World Map when zooming to select an airport.
Attempt #7: No Mods.
Clean reinstall of NVIDIA drivers because why not.
Launched the game.
Did not zoom in the World Map, typed airport names instead.
Started flight (vanilla Icon A5).
CTD after about 2 or 3 minutes of flight.
Attempt #8: No Mods.
Launched the game.
Zoom in the World Map, no issues.
Started flight (vanilla EXTRA EA-300).
Same airport as before, same flight pattern.
No CTD.
Flew about 10mns above a PG city for testing at various altitudes: no CTDs
Switched plane to the TBM930: no CTDs
Hope everyone else has a better experience.