just want to clarify, some flights with carriers do not accrue minimum miles. So if you fly 300 miles, u'll only get the 300 miles, not a min 500 or 625.
additionally, the 50% bonus as a MX Gold, is only on BASE miles, not on class of service bonuses.
IE
syd-kul 4,093 miles
C class bonus 25% 1,023
mx gold status bonus 50% (on BASE) 2,047