You caught me!
I’m a little bias because I, too, have used all machines and the only one that hasn’t crapped out and keeps producing quality cones is the Doob Cube.
I’ve been building original products for years and I stand behind those I believe in. When someone clearly hasn’t taken the time to learn or ask for help; and, when someone has negative intentions(works for the competition), I have to speak up.
I’ve been around the block with the Cube and 99% of the cones, using an average grinder, come out on point, literally within .03 grams of each other.
Additionally, cones are supposed to be filled to the top bc they still need a little tamp and twist, any bouncing device is counterintuitive.
Get you a machine (The Cube) that is 2 in 1: a screener and a sifter. This way you have only the ideal material for the ideal cone- no limps, no runners, no burnouts.
Also, if you’re not aware, when you buy a Cube the company offers to do the first round of cones with you, that way the machine pays for itself in the first run and you know EXACTLY what to do.
Thanks for the compliments on my longboards, I have a lot more to post! They are all pressed in-house and the art cnc etched into the veneer for permanency. They are made of multiple layers of maple, fiberglass and carbon fiber/kevlar 
Anyway, Do the Doob!