Even if he's convicted, nobody ever gets the max. And even when he does go, I would think he'd should be put in white-collar country club prison (or at least no worse than the "work release by day" situation that Epstein got), not gen-pop in a federal penitentiary. I'd think even in prison his living conditions would be much better here than they were in the embassy.
That's all assuming he doesn't cooperate with prosecutors to provide much-needed evidence of team Clinton criminality.