Here’s the link to the program: [UCSB Promise Scholarship](http://www.finaid.ucsb.edu/promise-scholars-program).
First question - why you and not your friends? Because the Promise Scholarship is for first-generation college students only.
Second question - what’s the advantage of this over the UCD award?
(1) Well, it’s more money, meaning you probably won’t have to worry about getting a job while you’re in college - not during the school year or during the summers. At UCD, you’d probably be expected to work during the summer to contribute to the cost of your education, and you’d probably be expected to take on a work study job during the school year as well.
(2) It includes the cost of study abroad - even if that cost is more than the cost of going to UCSB. So, no worries about having to apply for additional scholarships to cover the cost of study abroad - it’s taken care of!
(3) The program includes special classes just for the UCSB Promise Scholars, research opportunities, personal mentoring from faculty and graduate students, and special academic help (including tutoring) if you need it. There’s more information about the program here: [Woods Scholars Program](http://academics.sa.ucsb.edu/woods-scholars/introduction).
One other notable thing about the Scholars program is that it doesn’t require you to maintain some crazy high GPA in order to keep the scholarship. You just have to keep a 2.75 average, which, if you’re a reasonably good student, is probably pretty manageable.
Third question - do you get to spend the money you don’t use? Yes, in the description of the scholarship, it says that any funds that aren’t used for tuition, fees, etc. for a particular quarter will be refunded back to you prior to the beginning of that quarter to help you pay for books and other personal expenses. Those expenses include things like cell phone. And if you live off campus, you’ll get enough to pay your living expenses.
Fourth question - is your UCD award estimate going to be above or below your actual award? Usually, the estimates are pretty accurate. I’d suggest posting the details of your UCD award, so we know exactly what you received.
Just so you know, you may still be expected to take out some loans at UCSB, the same as you’d be expected to do at USD, but it’s possible they’d be smaller, or maybe you’d find you could get by without any loans at all - I don’t know. In any event, if you borrow money, the program would cover any loan fees. (That’s a fee you pay at the beginning just to take out the loan.)
My advice? Unless you really have your heart set on UCD, I’d take the UCSB offer and not look back! The research and study abroad opportunities put you way ahead of what you’d be able to do at UCD, and the weekly classes and personal mentoring mean you’d have the kinds of close relationships with professors that could really help you later on if you decide to apply for graduate school. It’s an amazing opportunity - I’d encourage you to take advantage of it!
And I love Davis, but the weather is nicer in Santa Barbara. 
