I could have done 2 more cheap pulls or do one 50 then get 9 Mythril for another cheap one.On the next two lucky pulls you mean?
Look at it this way, if your luck is complete shit for the next 22 instances (as determined at birth by astral patterns) if you pull on the lucky banners it'd only cost you 50 mythril instead of 100 mythril.
!!!
edit: wow it wasn't even on the lucky pulls
DISREGARD
Went with the latter and looks like I made the right choice.