I also travel United a lot but I would opt for the Priority Pass. In my expereince the Red Carpet Clubs in the US are realy not worth visiting. Crowded, no free alcohol, poor selection of refeshments, no showers. I get a free Priority pass from Amex which I can use in Continental Presidents Clubs and the like. I would rather sit in the terminal than visit the Red Carpet Clubs. I am used to the superior lounges in Europe and Asia.