I bought one 4 burner Bosch cooktop on July 2016, after 2 months, it started to give troubles like, yellow flame, full of black smoke and vessels are covered with black coating. 4 times requested for service. They are prompt at visit, but it takes 2 - 3 weeks to get the spare and we have to wait until then. Even after 2 years problem still persists.
My suggestion is to never buy the cooktop seeing the name BOSCH. Only name is there, no quality or service.