They are regarded as a premium boiler. The controls are complex and an average oi tech may not understand how to set it up. That said an oil boiler doesnt really pull much power. They do use outdoor reset which tends to run the circulator pumps longer per day but unless they are the old style pumps the new ECM pumps do not pull much power.
I have the Buderus oil fired boiler as a backup to my wood boiler..not really sure how that could have added to your electric costs. The controller on top of the boiler doesn’t draw much power. Circulator pumps?