I fly diesels and glow engines. I only began with the diesels after about 40 years with the glow engines. Here are some observations I would pass on: as a beginner, stick with something the guys at your field who will be helping you are familiar with; glow engines are more predictable in many ways than diesels, hence easier to learn with; they do stink, although some of that is controllable with a great deal of extra effort and care. The fuel cost is a "wash" because the diesel fuel costs more but the engines use a little less. Although you don't need ignition batteries, you will need to learn how to handle diesel fuel in a way so as not to lose the ether content. But if you fly certain events--especially endurance events--diesels have an inherent advantage. Or if you want an engine to turn a much bigger prop (at a correspondingly much slower speed) in order to get high torque and steady power, diesels are fine. I like mine; I also like my glow engines.