I care about the income tax not the SDI. I was very annoyed that they took SDI out of my check.....until I needed it. I will say it's been pretty painless and (for UPSers) while you are out on short term disability, it's ON TOP of the Mutual Aid so you are actually getting more net pay than when you are at work. FYI. I'm sure over the long term, I will pay more into it than I get out but so far this has not been the case.