I've been commuting on a bike with the exact same type of bend in the seat stay for a few months now and have had no issues with it. Before riding, I did take it to a couple bike shops for inspection and both did not hesitate to tell me it was perfectly fine to ride, however, given the liability issue, they were not able to assist me in realigning the seat stay.

The only issue that I've noticed is that the handling is a little bit squirrely if I ride no-hands, which I rarely do.