Oris review: Don't buy 1

My Oris Artelier Moonphase watch clasp opened with little provocation, until I was at a park and lock and took my jacket off and saw it fall from inside my sleeve to the ground destroying the crystal and scratching the stainless. They wanted $375 dollars to repair it, while claiming nothing was wrong with the clasp, though still under warranty. Should a watch come off when you take your jacket off? There is no safety clasp, perhaps it's an Oris faux pas, but World of Watches / Swiss Watch International should have fixed it no charge, or given me a new one. The watch cost me just under $850.00