The only reason the Rally is good at grinds is because they use the plastic polycarbonate, which is good for grinds, same for Delrin and celcon.
I’m not sure about the protostar, I think they just made it textured to improve grinds a bit, kind of like one drop’s projection profile but on plastic. I don’t own the newer protostar so I’m not sure.
Yeah but the Rally has the machined catch zone which is what helps for the grinds, not just the material itself. If they left it like the cups it would just be smooth like any other plastic.
Yes that also helps with grinds, but not very much on plastics as far as I know. The material is more important
Update: Still really loving the new Diffusion, so much that I just ordered a second one… now I will have the clear and the red.
Also, I used the Diffusion in the “old guy” yoyo contest recently. I filmed my contest entry while I was out of town, and whenever I travel I prefer to bring a good plastic and not worry about dinging a metal. Here’s the vid: beezy throws a yoyo II
And…I’ve repeatedly nailed this yoyo on the floor recently, without problems. Still as smooth as ever, durable plastic doesn’t mark too easily.
In general, I like working on difficult and new tricks on a plastic for a couple reasons… one is that I can just go for it and not worry about smacking the floor and dinging a nice metal. And of course, with a new trick idea I’m more likely to hit myself while smoothing out a maneuver…again, plastic is ideal because they don’t hurt as bad when you hit yourself on accident. Plastics are also good because they tend to lose spin more quickly with sloppy play…so you are forced to tighten up.
That all said, playing with the Diffusion is a joy and it is actually very forgiving of sloppy play due to the shape and long spin time.
So…the new Diffusion is not only my go-to every day carry, it is simply one of my favorite yoyos of all time. Just so fun to throw, and I can just go for it and not worry about it being too expensive to damage and/or that it will damage me. And I finally just nailed a solid Seasick on it…we’re officially bonded 4 life, this yoyo and I. I <3 Diffusion
Great update Beezy ! Similar situation here as i will soon own the white and clear. Love this yoyo 
