Worked for Sharp Electronics many years up to '98 and worked in the consumer electronics area which covered microwaves.
Be aware that a convection M/W must be vented. Manufacturers make vent kits for each of their convection units. It would be unsafe to operate a convection M/W in the confinds used by regular microwaves as the heat would be too great and pose a fire hazard. Consult the installation specs with your oven before purchasing it to make sure you have room to install and meed space requirements.