If all but one class were removed forever, which class would you pick to stay? Me: Demoman

All classes take skills (Yes Even Heavy :D....) each with their advantages and disadvantages so which class would be the hardest to master? I want to hear what you guys have to say any thoughts, reasons, etc. on why you chose that class?

I would say personally that either the medic or scout has the best looking cosmetic as most of their cosmetics go well with most others.