I have used Global Entry at LAX twice in past few months and have consistent experience as follows...
-the queue for Global Entry was long with flight crew members (in my case there were over dozen people)
-there are 3 kiosks for Global Entry at LAX and 2 of them were not working. No one could tell which machine was working or whether it was really machine or user errors
-there were people in the line who were confused and did not know what Global Entry is and clearly should not have been in the line, adding up to my wait time
-single working kiosk machine was difficult for people to operate independently, making the process even more slow
All said and done, Global Entry is total waste of money at LAX and nothing short of a scam. I paid for service that i do not get. I can get out faster in regular queues than in Global Entry. I will seek refund from authorities