Booked Ticket SJC-LAX
I found a ticket on Expedia from SJC-LAX for $165 and its nice that you can pair an Alaska Horizon Air with a Delta flight back to leave LAX later. I think using Alaska/Delta down to LAX will be more convenient as there is no shuttle bus to take to the American Eagle terminal. Also there are way more concessions as you have access to Terminals 5-8 so if your hungry there is something for everyone.
You also can book a Delta or Alaska flight down and fly on Untied if that is the least expensive way vs Untied Express.
Plus you can access the Alaska Boardroom, United Club and Delta SkyLounge without re-clearing security.
I guess American Eagle will lose their market share if they don;t get rid of their abysmal AE garage and connect the terminal to Terminal 3/4 with a bridge as opposed to a bus. I've seen people literally miss their bus because they thought the plane parked at gate 44 I. Nowhere on the AA webstite or reservation does it say you need to take an additional bus.
I also love how on Horizon Air they give complimentary beer and wine.
At SJC you have the new Club@SJC and then its a 5-8 minute walk to the Alaska gates and Delta gates.