I wish I knew the answer to that!

I'm not sure the difference is much more than marketing..

IMO....everything after the "SF" series was a downgrade anyway....

I'm not being mean though....I just don't think there's anything to talk about
between the "FX" and the "FXi"

I'm sure it's a respectable motor. Light it up and fly.

Best regards to the northeast!!!!!

'Race