As someone who has used both, I whole-heartedly believe that anyone who would put some marginal financial benefits of a CU over the ease of use, consistency and convenience of a big corporate bank is insane. So it appears we’re at an impasse.
The first credit union I belonged to, my balance was rarely four digits, more commonly 2-3. The branch assistant manager was absolutely amazing. She'd do me all sorts of favors, like insta-clearing parts of checks I was cashing.
Any major bank is full of pencil-necks who have the corporate rule book memorized and won't dare speak a word outside of the script they were handed.