OK...so you don't need to go too crazy then. Have you got a budget in mind? What about the speakers up in the dash? Or are you just gonna do the front doors and leave it at that? The two 3.5" speakers you may have in your upper dash / defrost vent panel make a huge difference in how your system sounds.
Infinity Reference, Alpine, Kicker, Polk Audio, JL all make good, middle line quality speakers.
Before I pick speakers I go listen to them at an audio shop, which is how I ended up with the Hertz HSK 165 2-way component system I have in my truck. They won't sound the same in the truck as they do on the audio shop floor but you will definitely hear a difference and be able to pick the higher quality, better sounding speakers.
You know I didn't even know there were speakers in the dash? Thanks for the info Maddog, I can't believe I'm just learning this, and I thought I knew my truck inside and out...I'm the kinda person who doesn't like budgets I'll wait as long as it takes to get what ever works best. What size are the door speakers?
2008 ram 1500 bighorn 4x4
2 1/2 level lift--hella 500ff grill lights--17x9 centerline grizzly-305-70-17 nitto terra grapplers--front air valance removed--tinted windows--custom audio system clarion vz401 head unit--pioneer 4channel amp and class D mono amp--memphis mclass door speakers--clarion dash speakers--kicker subs