It works really good it just doesn't fit properly into the 2 and a 1/2 inch bag you have to put it in sideways but that's OK cause it works fine
Large Cylinder Pre Press Mold ( 40mm Round Puck ) - Stainless Steel Made, Works with 2.5x4.5 Filters
I have both the 30mm, 40mm and find them great for pre-pressing. reduces blow outs and increases yield. I followed the cut off bottle tech you tube video and it works fantastic everytime!
I would highly recommend the pre-press. Stuffing the rosin bag by hand can lead to breakages during the press as you have plant matter crammed across the entire bag including the edges. The pucks this thing makes fit perfectly in the rosin bags, and it allows for expansion of the puck during the press. So yeah, this pre-press is worth it and I'm glad I have it.
The Large Cylinder Pre Press Mold is very well built and it looks like it will last a very long time. I would recommend this prepress to anyone that has press plates bigger than 3x5.