The CSP is a better earner and the sign on bonus of 20k more miles is worth about $300 in United miles.

Reasons to be made to get the United card. You check bags when you travel and have a bunch of flights planned (actual cash savings of $25 each way). You value the club passes (you can typically get them for $20 on eBay). You don't think you can reach the 4k minimum spend in 3 months.

No one can say what the better card for you is, but those factors are what I would use if I was determining which card to get.