I have a 98 with 4:88 and 33x12.5r15's. Cooper STT Pros- I like it a lot. It is nice around town. It is a little extra lower geared for offroad and running around town, and really probably barely more rpms at the freeway than 4:56. I guess you can look at it both ways where you are saving a few rpms on the freeway getting 4:56 or for a few more rpms on the freeway, but you are getting quicker starts. That is worth it for me.
Honestly I bet you won't notice any kind of a fuel difference from 4:56 vs 4:88's I think where you will really notice a difference is coming off of a stop. I don't think you will be disappointed either way, but I am not regretting my 4:88's.
I do wheel mine almost as much as I street mine, so I am probably a 60/40 street/offroad, and running pretty aggressive A/T tires.
Just for your info, my Jeep will go 80 on the freeway with no issues with the 4:88 gears in case you are wondering.
I feel I am bias because that is what I have, but I am just giving you my experience not really trying to sell you on anything. It is all just preference, but again I don't think you will notice much difference except taking off from a stop and maybe when you are out in 4Lo. It will be a little extra lower. That is precisely why I chose it.
My old YJ had 4:56 with 33's, and I wasn't disappointed with it either, but I do like the 4:88's slightly better.