In my opinion, UA has been great to me, and I am nowhere as loyal to them as I am to US. I just did 6 legs in 3 days, with every single leg delayed. I only flew on the first two legs as scheduled. In SFO, SEA, and ORD, I met outstanding agents who went out of their way for customers, regardless of status to make sure people got where they were going.
My case was complicated by the fact I had 5 colleagues from Japan traveling with me--all on different PNR's. In each situation we got on earlier flights, and made all connections. On my return Tuesday, I explained to an agent that I absolutely had to be home at night for family medical reasons. She called the gate and made sure I had the highest possible priority for standy on the flight which would prevent a misconnect, and by the time I got to the gate, I had a seat.
What she couldn't know was that my original flight lost its delay and left before the flight I acutally took, but the connection was late and I had no problem getting home.
I would also say that UA folks say "thank you for your business" more often than any other airline....they must want the business!
I am sure UA loses its share of customers, as does any other airline, but I have found US and UA the most consistent product over the past few years.
My best to you all....