I guess this is where I should provide some context..."noisy" means "the typical TL-01 gear-drive sound".
I've had 3 of them...I have plenty of new Tamiya pinions and new gearbox gears. I sanded the sides of the gears for clearance, shimmed them the right way and even the "old" gears got quieter. The new one is even quieter than that.
They're not Pro 4/Yokomo quiet, but they're TC-3 quiet.
You could see marks inside the gearbox halves and on the gears where they rub.