Wow thanks to everyone who replied and took their time to explain it in so much detail. However my current system is an axle back with a straight through muffler, not a muffler delete, so the effect of a resonator delete might not be the same as for you guys. But your feedback is still very useful.
another question i have is that the sound of the exhaust comes back to almost stock at high rpms which i find weird. Is it the axle back pipe being larger that the rest of the pipe? Im not sure how big the pipes are from the 3rd cat but the exhaust shop did install 2.5 inch pipe after the y split. Any ideas?