Devildog - Try removing the duct between the airbox and the inner fender before you clean the filter. This seems to be the intake restriction. It was mine. Post your results.
Sky - On a stock truck - no difference. It does sound better, of course. If an air filter substitution made a power (which would also equate to fuel efficiency) improvement that could be felt, let alone measured, the truck would already have a bigger element.
On a BOMBer like yours, you probably need the increased flow to match your increased fueling. Did you remove your fender duct yet? Try it. Mine would still pull the minder down 1/2 way with the new filter. Removing the duct fixed it. Got a bit more turbo noise too. Had to put the silencer ring back in.