Well, from the UA flight time you mention, it sounds like you're going to Hawaii, so I don't know if you're suffering all that much ;-).

That said, the RCCs at SFO are relatively nice (compared to others in the system). You will have two to choose from, one in the int'l terminal and another in the domestic one. I don't know if you can shuttle between them, but if you're in the airport for more than 4 hours I would call it a decent deal.

However, I do not know if you get internet access with the day pass.