Extruder Head Technology

Hi guys!

I am new to the RepRap community and I am very eager to learn things related to FFM technology. However, I've been having a hard time with respect to finding things in the area of "Extruder Head Technology". I tried to research it in two parts such as "Cold End Tech" and "Hot End Tech". You get to learn a lot about the specific Cold Ends and Hot Ends. However, in my application, I'm trying to find a comparative platform in which I can see what the parameters of comparison are and for example, which hot end is better under what performance conditions? etc.

I know most of the innovation that happens in the world of "3D Printing" is by DIYers or enthusiasts who have innovative ideas and come up with amazing results. Are there any good sources? I've been suggested to read through the forums here but there's just so much that it's a little bit overwhelming. Any information or links would be appreciated

This research is related to my Thesis. I am a Masters Student studying in Milan. Any help would be appreciated, thanks!

Did you find RichRap's hotend article in RepRap Magazine? The magazine has a forum on this site with links to all three of their issues.....

Yes I did. The source seems to be about one year old. Is there anything more up-to-date? I assume the technology has changed quite a bit since then, right?