I've read on numerous forums how to take the gearbox out...and even on mechbox.com they advise to set up a thick book on a table, and after removing the rear plate, BANG the shit out of the stock, until the mechbox pops out.
I'll comment here as i did there...At least with the JG, there are 3 bolts running through the stock, including the one that runs through the mag release tab....simply by unscrewing those, you can crack open the stock enough that the mechbox easily slides out. Easily, as in, no banging, or potentially damaging your gun. It pops back in just as easily, after which, throw the nuts back on the bolts and screw them back up tight. It separates at the bottom of the stock anyway, the top of the stock along with most of the gun's body is fused/glued together, and isn't designed/needed to be taken apart. It pops back in just as easily, after which, throw the nuts back on the bolts and screw them back up tight.
If those screws don't exist on TM's or CA, then I say HA to you. I've had my JG for a couple months now, LOVE IT, bought it on ASC from someone who won it and didn't want anything to do with an AUG. Looking at pics from last years boarder wars is might even have been that very JG AUG on the prize table lol...I should ask him.
Further comments - it chrono'd 335 out of the box (.20s) shoots accurately (enough that with a 3X scope, i'm getting scope kills every game, and this is with a pure stock set-up, and even b4 i completely figured out the hop-up),
The gearbox noise is hardly going to deafen you but the previous statement was correct, it is right under your ear.
Issues I've read about and can agree with, are the front handle, since it allows itself to fold up or down it does wobble a bit - I couldn't care less, its still solid to use and won't go anywhere but a half a millimeter back and forth...the other thing would be the outer barrel doesn't like to get bashed into things, apparently it's brittle and can crack/break...no firsthand experience, but i keep it in mind. What DOES like to get bashed against walls/the ground though.
Battery compartment is stingy. But I'm taking measurments, and look fwd to hacking up large battery packs and re-configuring the pack with a hump, because It'll fit. I will make it. And I'll make them for others if they'd like high mAh custom AUG batteries
If you havn't noticed, I love my AUG. Wouldn't trade it for a generic M-anything, anyday.