There are many advantages to useing the BHAF such as free flowing air, maybe a little faster turbo spool up but so small it really can not be called significant.
I have found there is no EGT improvements.
Alot more noise.
It sucks hot air in from under the hood and is right next to the hot turbo and exhaust.
I have to wait longer for the turbo to cool off before I can shut down the motor due to hot air being sucked from under the hood instead of cool outside air, and expecially after towing.
I have changed back and forth many times this summer from stock box to BHAF and I came up the formentioned.
I am putting the stock box back in for good until I fabricate a shroud to go around the filter and can suck air from the outside.
Ron