your intake will generate the sound - Ram Pod = louder / CAI = quiter.

Then your headers/extractors will then flow the noise to your 2.5 system.

If you dont have a resonator then the noise will still continue to travel to the muffler.

depending on your muffler - cannon = loud as hell or twinloop = nice quite sound.

Saying that - a resonator depending on size/quality should be able to shut the fhukker up but yet again a str8 thru cannon will definately make the incabin noise annoying.

Power vs sound = what is it that your after?

2.5 will give you abit of lag from 0-80 but after that it should flow nicely as the engine is working harder.

for a daily - i would recommend 2.25 rather than a 2.5..

but this will depend again on what bolt on mods you have.