The choke unloader causes a lot of people trouble. When you first crank your jeep, the diaphragm and its arm must keep the butterfly valve open 7mm (9/32"). Too far closed and the engine will suffocate, too far open and the choke is useless. It is very finicky.
Getting the accelerator pump adjusted correctly is another one. You have to really read your Chilton's manual and set those two screws inside the carburetor just right or you will have either a nasty flat spot just off idle, or your carb will "run out of steam" early.
My other complaints with it are not so much the carb 100%, but the function of its stepper motor and its "communication" with all of the sensors, etc. that feed the computer. This is a crude afterthought of an engine management system and if one of your sensors or the connections thereof start acting up, the carb is where the malfunction will appear, with it running too lean or rich. My jeep did okay after I de-emissioned and set the rods in the stepper motor to a permanent position, but by that time it had 130k miles and, like Bob K mentioned, other wear-and-tear factors start coming into play.
Currently an '86 CJ-7 and a '77 CJ-7 Golden Eagle---#4 and 5 following a '01 Sahara, '90 Sahara, and '85 CJ-7....