Too many local cowboys zooming out of the valleys and cutting in front of other aircraft on approach. Had to go around once after one of them appeared from such a valley undeneath me while I was on a long final.
Too ill disciplined there for me to feel completely comfortable.
That has happened to me at a place with no mountains around at all. Ill disciplined yes, but not LSZS specific IŽd say. Never happened to me in LSZS, uncomfortable close(thats LSZS specific) heli traffic yes, but always announced and in sight.