sorry but don't is important the air in the ball , because if i use a strong ball ,for me is more difficult , because i use a soft ball , if mp,ars,tom folan or another freestylers use a soft ball have more problem at close good combo. if you usa a ball size 4 and not 5 size is cheat.
for the same motivation we can use adidas shoes or nike , nike are more soft shoes , but if a person use nike don't usea trick for play a better freestyle