I used the EZ-Setup method when creating an employee contributed SIMPLE IRA deduction. I noticed during this EZ-Setup wizard that the Taxes section only has Federal Withholding, Local Withholding and LST checked. State (Pennsylvania) withholding is not checked as a default. When I ran payroll I found that the state withholding amount isn't a true calculation for our state (3.07%) when using the adjusted gross income. Why isn't State withholding checked in the EZ-setup wizard under taxes? I don't want to change the QB default settings unless instructed.
I also suggest you visit this article: How QuickBooks calculates payroll taxes. It has tables for the calculation methods, as well as a short description of what you can expect to see on your employee's paychecks.
In case you have clarifications or other concerns, feel free to comment below. I'll be sure to get back to you.