"Mobbing is ALWAYS faster than soloing"- some wise mapler
so why bother with flash fist when you can mob and kill using summer sault?
On top of that summersault works with other weapons (oh what a 86atk tuna at lvl 10? o-m-g)
I can almost guarantee that using a fist vs a 86atk tuna summer sault u'd get more damage PER hit using the tuna (haven't tested).
Oh by the time tuna goes obsolete you already should have learned new and better moves than flash fist.