Level Off at MDA
Yes you CAN level off at MDA legally and fly level to the MAP - dive and drive but this has been dropped by any self-respecting airline for years due to the number of accidents it produced.
A Constant Angle NPA - CANPA or CA APPROACH is flown like an ILS using (usually but not always) an increment of 50 ft added to the MDA so that one does not infringe the real MDA in a GA at MDA+50.
Much safer.