Just like with PMUA cards, these cards are set up to cater to different people. The same difference used to be the case with the old Club, and IIRC the Access card too - those are more for people who value status and benefits over mileage accrual. This was more with those old cards, for instance there was at least one that had much better EQM earning, but still generally applies to different groups of customers being targeted.

For instance, in my position I'm nowhere near getting any kind of elite status on UA anytime soon, so I would rather have my Select card earning more miles on most things. Likewise, I don't personally have much use for the UC membership and that higher fee. However, if UC membership is worth something to you, then the Club card might be good to have as well.

OTOH, the Club card does get you 1.5x on everything, so now you'd earn extra miles for Target, Ikea, car repairs, "random things", etc. where you wouldn't with the Select card. So back to my situation, that would be a nice complement for those situations where I'm not going to earn double on my Select card. It just so happens that my personal usage falls mostly within the 2x categories of the Select card, and of course the 2x for Star tix and 3x for UA tix. But if you don't happen to utilize those as much, the Club would be better.

In short, the Select is going to be better if you're trying to rack up miles. But if you are willing to pay for UC, priority boarding, free checked bags, and 1.5x on everything (2x on UA), then the Club is a good bet. It just depends on your situation.

Sorry for duplicating some above info - my browser was being slow