GS is the only reason 99% of my annual travel is on UA as opposed to a 50/50 split between UA and AA with the occasional random DL. Even the Continental-heavy management team post merger admitted that the UA GS program was a huge value proposition over the rest of the industry's efforts to take care of HVFs..
For me the jury is still out as I just got the GS invite for the first time but no doubt about it I have already spoke to Mrs. Nomad and we are going to take full advantage of the program while we have it. Already planning several international trips. The only problem is the invite came a bit late and I have already booked several trips with AS this first Q 2019 and we don't have many GPU/RPUs left. I am actually pullling several of them off short hop local flights which as a 1K I was throwing them at everything I booked because they rarely cleared and I was dumping them at the end of the year. It is my hope that as GS this won't be the case but as I read some of the GS threads it is almost comical that you do see some of the same complaints about clearing instruments that see on the 1K threads. Time will tell........