I don't bother with upgrades when on single business travel. I always get at least a club level or "premier/deluxe" upgrade without asking and that works fine for me as I really don't need a suite for just one person. OTOH, when travelling with the wife or family, I'll ask for a suite and it's usually accommodated without any fuss. So like clarkef said above, makes sense that rev mgmt wants to please those who want to be pleased so ask when it makes a difference for you. That's a win-win all around.