ST, hopefully I'm in the thread you were talking about over in the mod 91-05 thread.
So, here we go. You will never get the rumble of a v8 out of a v6, so as said in other threads all over, it depends on what your taste is. Flowmasters may have a lot of raspyness but it can become a drone very quickly. That, and everyone has them! Ya want a good sound but you also want something custom to your explorer right?! Magnaflows are known for a good deep sound through a lot of the rpm on the v8's and they have tons of flow. I haven't seen people around my area with magnaflows so I don't know how ricey the deep sound would be on an ex. Then there's glasspacks. Glasspacks are known for being LOUD. But cheap ones can sound really ricey even though the glasspack is meant to take out some drone and high tones.
Then there's whether you want to go catback, dual out of the muffler, or true dual and what pipe size to use. Anything other than stock will be good for more flow. But you don't want to go too big so the exhaust cools too fast and doesnt have the push and scavenging effect that you need to keep the exhaust flowing. For the catback system with one pipe a 1/2 inch more is plenty big enough and will give you more deeper tones and better flow. The single in dual out muffler can have 1/2 inch bigger than stock coming in, and then the output should only be a 1/4 inch bigger to keep flow and sound. If you go bigger there will be too much flow causing drone. A buddy of mine just got that setup on his f150 and the output pipes were the actually the same size as the original pipe to keep a good amount of flow and lots of sound. Now there's true dual. My explorer came with no y-pipe. I have one pipe coming down from the manifold, to a cat and then the pipe went out to the muffler, and the same on the other side. Now I have that, going to the xpipe, and back out to two straight through mufflers out to 3 inch tips. It sounds deep at low rpm, loud as im accellerating. And quiet at highway speeds. And then when I tromp on it holy crap it sounds great. I'll get a video up asap
