Hks filter or Oem box

[scooby doo]

Advice needed
I have a 1993 Wrx running 284.2bhp @ 0.9bar on a jdm chip,
I plan on running 1.1bar now its got its new clutch,
but my question is am i better of ruining OEM air box and uprated panel filter or carry on using my hks induction kit?
I'm only aiming to run 300bhp from the car.
Here's the mods it has just in-case any of them could affect me from running the OEM box,
Standard td05 and Tmic,
JDM Ecu
Walbro 255
Aeromotive fuel reg set at 3.bar
Full 3" exhaust with bellmouth and no cats
uprated clutch
Hks filter and fliter pipe,
No a/c
no carbin canister
oil catch can
ported and wrapped harvey headers
throttle body coolant bypass
uprated plugs
Intercooler spray
all new service items
no dump valve