Not 6mm paint bbs, sticky peanut butter!
That was more a joke, anyway.
The point is that after 20 years, you'd think there would at least one competing gearbox design, or that companies would at least put some work into ironing things out and working on quality control.
I don't want to sound like I'm saying "boycott airsoft! Screw the cloning Chinese for their shotty (ha) QC on my gun! Let's get a petition started for airsoft manufacturers to develop something better!"
I'm just saying that the progression of airsoft is fairly non-existant, and this can be shown by it growing up alongside paintball, which is essentially the same thing, except that it uses gases to propel its heavier projectiles, instead of a motor to wind a piston.
If I were a parent, and I had two sons, and one day I walked in on the two of them drawing. One was drawing circles, and showed it to me all excited, saying "look what I drew!". He had coloured the circles in, but a lot of the time the circles weren't perfect circles, and sometimes the colours would stray outside the lines. Then I look over at the other, and he's still hunched over his drawing. I walk over and see that he's drawing a beautiful landscape, with vibrant colours and amazing detail.
I would turn to the first kid, and yell "YOU'RE 20 YEARS OLD. FFS. YOU'VE BEEN DRAWING CIRCLES SINCE YOU WERE 3. AT THE VERY LEAST, YOU COULD HAVE LEARNED TO COLOUR INSIDE THE LINES. LOOK AT YOUR BROTHER."
And then I would shame that first child, and make the second child my prize. When people asked how many children I had, I would proudly say "I have two children", and the first child would smile. But then I would point to the second child and continue "This boy right here is as good as two children!", and the first child would go be sad, and hang out with his group of friends that drew even crappier circles, and praised his circles with things like "well, you can either draw a circle, or a square, and a circle is more perfect than a square".
I ramble too much.