Good question as I was wondering the same thing, I have a 95 wrangler with the 2.5. It has enough power for me, more is always better, but I like my little 2.5.
I used to have a big block chevy 4x4, but I have grown up since then.
Does the AEM do anything at all for gas milage ? I ask as I'm teetering on getting one and if it helped that could be enough for me to justify it.