Might as well go big with 500.
Not really logical. He can get big on 250, so why get more suppressed.
You may acually want to try something less suppressive for a trail run. Hell, you can grow on 25 mgs of dbol for 4 weeks with the right training and a few supps. I think first cycles have become overkill. They should be a trail run. You've got plenty of time to go up in dosage and duration.