While I love how US at least gives you the chance for F upgrades on every flight, I have to admit that UA's domestic first class is much nicer than US. I was on a quick flight from lga-iad last saturday (the 1 out of 6segs that was on ua) and i was in first class. Even though it was such a quick flight (boeing 733) they still had glass cups and snack boxes for all in F. Us has leather seats but honestly no comparison to UA's cloth first class domestic. But it all comes down to the fare price! Being out of clt ual flies mainly 733, a319 and 735 to DEN or ORD. Being 18 I am forced to go with the cheapest fare on either US or UA (US always wins). I guess you're just comparing what you will give up (cheap fares) for nicer seats.