If you got a DUI on federal land or were otherwise arrested for a federal DUI, get ready. Federal DUI law is far more strict than state law when it comes to probation. Most of the other penalties are the same with a federal DUI as with a DUI in state court.
Again, the difference in California is probation. Probation for a DUI in federal court is formal, rather than informal. That means that you have to report to a probation officer, answer personal questions about your life–especially drinking and drug usage–see your house searched, and report to the probation officer on a regular basis. You will also be unable to leave the country (or even the state) without permission from the court and/or the probation officer.
If you are looking for an attorney be advised (a) that public defenders at the federal level are excellent–I would not have any personal hesitations in using one; (b) if you are using private counsel, make sure (i) they are admitted to practice in federal court and (ii) that they practice there regularly. The rules of procedure in federal court are very different from state court.