Just enquiring what kind of exit indicators do people use when letting proifits run until a breakdiown of a trend?

I've just started using the 50 ema. I trade daily charts and like to get to breakeven using various S&R points....and then let teh 50 ema catch up to breakeven and i then trail that for an exit strategy.

I suppose it makes no difference really. Or does it?

In my own head im thinking an instrument can bahave anyway and we can only tell with hindsight what the best indicator to use.
So as long as i am using some indicator that keeps me in a trend while its going in my favour - anbd gets me out when the trend breaks down then im thinking i cant do any more than that.

Am i oversimplifying this? Or is teh above a fair analysis?