Well, the best that can happen is that you're found not guilty, but barring that an unconditional discharge is spent immediately - a conditional discharge is only spent at the end of the conditional period.If your case goes to court, the best thing that can happen is a conditional discharge as this is the only instance you can answer no to any question asking about a criminal conviction. Which means you can work and travel freely!
Whether conditional or unconditional, it is still a conviction.