For me it's the history that I am learning while researching a project. I am currently researching the spitfire (MKVB to be exact) and the knowledge and fascinating facts I am finding are a treasure trove of history. Not to mention the pride I have when something that started with a box of sticks and or plain ole pices of wood become a magnificent flying machine. trying to get the model flying in a scale fashion is a challenge as well and not just "punching holes in the sky". I have the arfs to do that with, and a crash is just no big deal with an arf as long as the electronics survive. To get a taste of this go ahead and add some detail and changes to an arf and make it your own. This will hopefully give you the "SCALE BUG".