I used BB bastard for all the time.
The weight of BBs that I use is depend on the game.
If the game is not restricted how many BBs you carry, so I used .20 g. I like full Auto on my gun.
If restricted, I used .25 for indoor game and .28 for outdoor game
For GBB, sometime I used .28 or .30 , it's depend which GBB I used also.