Hey there man, that's a good question. Really it all comes down to the sound you're looking for. One good way to get an idea of what different systems will sound like on your truck is to go on YouTube and check out some vids of the setups that are out there and see which one you like best. You can also check out the HEMI exhaust mods section to get some ideas and recommendations from other members, here's a link: http://www.ramforumz.com/forumdisplay.php?f=141.
My truck has an after market muffler I've never heard of. Whats a good muffler for a deep muscle tone ? I know flows and borla sound good on fords but I'm new to the dodge scene. Any help on ideas would be appreciated.