Extruder comparison

[Andycb]

I'm in the process of designing my first 3D printer and I'm now looking into the various extruder designs but there doesn't seem to be anywhere (at least that I've found) that compares the different designs. I know there's lots of different ones but I think they're often variants of other setups, such as the Wades and Bowden extruder's.

So if anyone could direct me to any information comparing the different extruder designs and explaining their pros and cons that'd be extremely helpful.

Thanks in advance
Andrew


*****Edit*****
I'm intending to work with PLA and ABS