The main advantage to using a solid state glow driver is that it will turn the glow driver off when the radio power is turned of. This is unlike a mechanical servo driven glow driver switch which can be left on after your flight and drain your glow battery dead. However there is no reason why you can’t just use a heavy duty microswitch and a servo to turn on your glow system, just be careful to make sure the system is off after each flight.
You may notice that the driver has two heavy duty leads that I added on the left and right below. These are the glow driver circuit leads that connect the driver battery to the glow plugs. The LED at the top lets you know that the driver is operational (this is handy for setting up the activating point on your throttle channel). The lead just below that is the throttle channel lead which plugs into the receiver. The lead below that is for trickle charging the driver battery in the plane which is connected parallel to the “battery in” leads.