Personally, I've had too many near-death (almost :P) experiences with saddle slips. Falling off sucks. Being on the side of a galloping horse because the saddle slipped when you began loping? Now that REALLY sucks. Probably the scariest experience of my life, and it's happened twice. If you're doing Western events that involve speed and turning (ABSOLUTELY when you're barrel-racing), I would reccomend a breast collar. Better safe than sorry! And IMO it kinda looks cute, too!