For a long time I set my stops outside of any so called support / resistance. That kept me in some big draw-downs.
Then Spike said tight stops. He said it so many times that I had to try it.
Now I get kicked out often, but commissions are reasonable so I can jump back in when I should have stayed.

So my real answer to stop placement is, I don't know. If you have a profit, take it and run and start looking for the next trade if you are uncomfortable.