That would all depend on how you want to use your CJ. Daily driver with occasional offroad adventures? Rock crawling? Dirt roads at 65mph? How much "oomph" you want also makes a difference. Also, do you have (or have planned) any performance mods for your engine?
Most people would warn you off from Holley carbs saying that they are "too tempermental" or don't work well offroad. I would disagree. I have a 350cfm Holley 2bbl on my wife's '79 with a 258 and love it. Sure, it took time to tune, but not THAT much time. I put in extended jets, notched float, and spring-loaded needle and it doesn't bother me at all in any conditions. The electric choke and the right jet sizes (I live at 5000+ feet currently) certainly help, too.
I like it so much that I'm popping a 4bbl Holley on my '77 with a 258 soon.
Your results and needs, of course, will vary...
If you're looking for something stock, reliable, and good all around, the Motorcraft 2100 would fit the bill nicely, too.
If you're looking for major power and "coolness factor," go ahead and get the Holley Truck Avenger, but (a) be prepared to pay for it and (b) be prepared to have to tune it (or have it tuned) for your engine and conditions. Then again, all carbs will need to be tuned for best performance.
FWIW, the 2bbl Holley and HEI distributor on our '79 helps us get nearly 20mpg in mixed driving every day. I'm hoping for that much on the '77 with the 4bbl, too (since the secondaries won't open up much, unless they're "wanted"