There is no harm in stamping your passport with a different designation. A lot of people are experiencing that. This is so because your company may not have a visa of the same designation as your position but reality is, you loose a lot of benefits having an engeneer visa. For as long as your contract with your company is what you and employer had agreed upon.

There are many people in Doha who cannnot even get a visa. There are companies who cannot grant visa because they are not allowed for another one and are force to hire even uncompetitive people under someones sponsor.