Personally I think GBBRs are a lot easier to take apart and clean. I can strip, clean, regrease and reassemble my WE m4 a hell of a lot faster than I take down an AEG and reassemble a gearbox.
Balancing that however, is the fact that you need to frequently take apart and clean a GBBR, at least every 10 mags or so I do it. With an AEG you can go tens of thousands of rounds before a problem is encountered.
Not for glory, nor riches, nor honours, but for freedom alone, which no good man gives up except with his life.