new on anbernic

Hi there
im getting my rg405v in a minute and i am wondering if i have to flash the os on the console or how do i add custom os? gamma os is probably what i want or i maybe happy with the original os ? just heard that gammaos is good for playing ps2 games that i want to do. or else i could play the snes games on the rg45xx or something? please recommend me for what to do

kind regards

​