Learning Radiant Editor

I have recently done some research on development companies such as Activision, ID, and Infinity Ward. Judging level editors by reading what Activision had posted on their site, it seems that they prefer, in order:

1)Radiant Editor
2)Unreal Editor
3)Quake Editor

Following this advice, I have since been learning tutorials from MODSonline.com and 3DBuzz.com about the Doom 3 Editor since it is Radiant-based. I already have the game and it comes with its own editor- also I like the detail that was achieved in the game. I immediately noticed that the editor has a simpler interface than what I was used to (Valve Hammer Editor). The feature I am most impressed with is the ability to Compile the level in a small window and run through it as if it were in-game. This is extremely helpful for fine tuning the color and distance of lights, etc., to get just the right feel. The editor seems to require a lot more scripting than that of Hammer, where every object seemed to be pre-programmed and the user just throws it in the game and it works. With the Radiant editor, I will be able to learn more about the inner workings of each level and have finer control of the output. At the moment I have a test level built but am planning on using the editor to make a level that has a completely different feeling than that of Doom. There is also a simple way to import 3D models from 3DS Max which also has me very excited. Stay tuned for my first finished level!