I currently have a 2006 sedan. I have read that getting a Coupe midpipe for 2005-2006 sedans is next to useless.
If I had an option to get something like a magnaflow glass pack muffler instead to replace my stock resonator, would it be better?
My current priority is to give the car more loudness without a full exhaust system.

 

Coupe mid pipe isn't useless, like all others including Magnaflow it just changes the exhaust sound, which appears to be your goal! Like intakes, midpipes offer little if any WHP increase!
Gary

 

If I had the option of getting Coupe midpipe vs magnaflow glass pack for same price, which should I go with?

 

Just swap the resonator with a Magnaflow or Dynomax resonator, that should get you some sound increase without drone or rasp.

 

Do you have any specific reccomendations?

 

18" usually works out well. Pretty popular on TL's and V6 Accords too. Gives the engine some growl without being excessive.

 

One thing for sure the coupe mid pipe won't cause you to have any rasp! I gave my mid pipe to my son-in-law and his sedan sounded (*)(*)!
Gary