I prefer the UA hard product. I prefer the AC lounge. I'd give a slight edge to AC onboard food, but I vastly prefer the Signature Suite food to the Polaris Lounge food (or onboard Polaris food), so AC lets you have a good meal on the ground, and skip service entirely for the first meal on board. But food preferences are definitely very subjective.

But at the end of the day, AC would only win for me due to the MM status. I live in SFO, so I'm giving up a lot of time to fly AC over UA on an AKL trip.