I think it would be pretty simple to open up the case that the mic is in, unsolder the three points (R+ L+ and Ground) of the headphones and solder in a nicer set of your choice. Carvin makes a fantastic set of single driver in-ears for $40.https://www.carvinguitars.com/products/single.php?product=EM902 Not too expensive to to hack off the 3.5mm jack and solder it in. Then you get premium sound on your G1 with a mic for fairly cheap. Tell me what you think.
Wow, that's quite the discount there. Only thing I'd worry about is that those are 16 ohm 'buds, not sure of what the impedance of the stockers are. If they are a high-resistance 'bud, then those carvin ones might make the amp in the G1 overdrive.
Do you think there would be any difference between using those buds the modified way and using those buds with the mini usb to 3.5 adapter?