ya i think apexi is a good filter. being inside the airbox is fine, it keeps hot air away from the filter, colder air=denser air=more power. if you can find hard pipes for the intercooler i probably would, your lag will drop alittle and youll have a little more consistent power i think. all these things your doing are going to make you have a bit of power tho, you think its fast now, wait for that full 3" exhuast upgrade