In my opinion AC's hard product is very competitive with CX, service could go either way depending on the crew you get and your personal preference, but the one standout, consistent difference is being able to use the lavatory 6 hours in and not have urine pooled on the floor. I am not one to get worked up because some grumpy FA didn't speak to me in pleasant tones of voice or whatever, but the disgusting lavs on ULH flights is something I find very problematic on AC/UA/DL.