I spent part of last Monday at Peter Pugger plant in Ukiah,Ca . They made a main seal bracket for me on the spot as well as hooking me up with all new seals and cord.I Talked story with them on all models. I have a new to me used VPM -30
I work with Porcelain and they suggested if I want to store clay in barrel use their stainless steel model.as it pits it faster than other clays. The downside of the smaller hobbie size VPM 9 is it only hold a pug of clay. I know a potter with that unit and it small size is an issue. He wishes he got a larger size. The next one up VPM 20 is 600$ more but holds 45#s which is a fair amount.
They told me that the small hobby model VPM 9 is what they sell the most at this time-thats the largest market segment.
Studio potters and schools buy the larger ones
If you are using Porcelain get the SS model for sure.
I'm storing 1/2 porc and 1/2 white stoneware in mine-it will pit it and I do not care. Peter Pugger or anyone for that matter can sandblast the aluminum barrel to smooth it out down the road -thats what they told me at Factory
Great folks and quality stuff but they are not potters they said.The owner was out when I was there but I did some some mugs made by potters I knew over 30 years ago in the mug collections .
25#s of clay is such a small amount to process as Colby stated above. The machine size is not that different from the smallest to the next one up-remember not all the clay gets extruded as some stays behind so you will be getting less than a pug.