I personally think they arent. I went for the BAe immediatelly beacuse its the biggest and most profitsble S plane. Although, due to the new update SaaBs are great for farming gold planes. Since you can now get one gold plane for 15k insetad of 23k with the ATR.
Edit: a BAe can yield upwards of 1000 ₩ on certain routes, it has the same range as the others if not more and is also faster beacuse its a jet.
For a detailed comparison you can check the excelent topic by @NocturnalNinja. He breaks down all the details of profitability.