Like Jesse said there are arguments on both sides, just like the tubing debate, the tow rig debate, the tire debate... blah blah.
My minds made up and
I/(me) have come to the conclusion that a V8 in a "trail jeep" is just a novelty mod for those who have money to blow; or parts laying around to use. In a racing configuration I can totally understand having a 5.3 or any V8. The ONLY thing all that extra HP is going to help with is sounding great, going faster and breaking stuff.
This 4.0 I'm rebuilding is a 2004 model, I'm not going to stroke it, but will do a CAI, Throttle body spacer, zero cat, and flowmaster 40. The 4.0 is proven, and has MORE trail miles attributed to it than any 5.3 ever will. It'll go EVERYWHERE a similar Jeep with a 5.3 in it will go and I don't feel like I'm settling at all.
I repectfully remove myself from the debate and take my place as a thread spectator.