I said tons dude.....tons. This is a commercial setup for actually bagging soil for sale to the public. The actual first efforts at packaging a suitable soil made in the USA. You can do that when you get it home.
I know that but of course you missed my point (as always).
What my comment is to make it more efficient for just a little more money...much more important if it is for commercial use. Why run an aggregate through it twice (or 3 times) if you can do it once?
Also, note that the finer the material...the slower they move down the ramp. Thus the ramp slope (for the fines) is normally more stiff than the sifter. But I guess he knows that already...just didn't do it.
I know about the vibration factor also but it really depends on what you are sifting. The walls of the lower collector is also very low, I see it as the production bottle neck. Hate to stop just to manually push the fines down the chute. If it doesn't have much fines, then this should be okay...just not as "flexible".
Good luck!