I joined SDFCU about 18 months ago. I absolutely love um. I have a CHE & SAV, along with their 6.99% Visa card, 2.9% used car loan, and two installment loans with them. While it was a little leg work getting in, once you're in, they want your business. They're loans, including my auto loan was the easiest products I've ever used. Absolutely quick and easy. I can't say enough good things about SDFCU. I don't use them for my main CHE & SAV as I'm 1500 miles away from their nearest office, but I use um for the low APR CC, auto loans, installment loans, and soon to be mortgage.
As for asking you for information concerning your other accounts, that's strictly if you care to use that option. It's not mandatory and it's there to help you keep track of all your accounts in one place. I initially used it, but it kept falling behind and would repeatedly need me to update PW's and logins for my other accounts, so I stopped using the service. But fear not. This has nothing to do with whether they'll loan you money, approve a CC app, car loan, etc... They have no access to these accounts or the information contained inside them. Best of luck. Feel free to ask any other questions concerning SDFCU. I've done quite a bit of business with them and plan to continue in the future. They make it extremely easy once your in.