Droid Engineer Archive

There a good informational web site with all the info on droids? I'm just kind of overwhelmed with all the R2, r3, r4, 3po, yada yada. 5 lvl 3 modules, cluster module this level 5 module that, in one ear and out the next. I don't get it. I don't want to pay 45k for a droid if it doesnt serve my purposes any better than a 8k droid.

Any good web sites that really draw out why I would want an R2 over an R4, what level 4 module gives me vs a level 6 module, etc?

Right now I'm shopping for a droid (one that's not stupid looking) with a quality weapon, droid, general crafting station module. I am sure I'm asking around for the wrong thing, though and so getting prices on stuff that may not be the correct choice for me.