The SL is a MUST. Losses are part of the game. We can`t win them all. With a good money and risk management all will be fine.
I can’t think of trading without a stop loss. It doesn’t only limit my losses in unfavorable conditions but also gives me the confidence that I won’t lose more than I can afford to.
No stop loss only margin calls ?haha That's risky, your emotions wouldn't let you pull out with a loss. Most traders than become investors when they go in drawdown and then they don't want to cut their losses hoping it will go back to green one day.
The only good thing about SL’s is they allow you to reset psychologically; regain composure if the market shook your emotions, rattled your confidence, or provoked seeds of self doubt.