No matter what your goal is, you should be thinking on the key parts. Most key is the hopup. That is what you should pay most attention to. Two other things that are important is the barrel which needs loads of attention, and then you should consider to shim the gearbox properly to make it quiet and smooth.
Once you've got those things sorted out, you can start considering upgraded parts, since today most stock-parts are plenty good for a reliable rifle.
EDIT
Also, if you're planning to make it a DMR, you need to look at "THE Holy Grail of building your DMR AEG". Most can also be applied to a regular AEG though.
Once you've got those things sorted out, you can start considering upgraded parts, since today most stock-parts are plenty good for a reliable rifle.
EDIT
Also, if you're planning to make it a DMR, you need to look at "THE Holy Grail of building your DMR AEG". Most can also be applied to a regular AEG though.
