Think about this, though. It’s not really about the correct psi, is it? If a chart says that you need X psi for a given amount of material, and you just crank it right up to that psi, you’re going to have a shitty return. You gotta slowly increase pressure, knowing when to wait to let it start flowing, and when to increase pressure to get it to flow more. Go to fast, get a blow out. You can use the gauge towards the end of the press, but after a time or two, you’ll know how much pressure to add based on the feel of the handle. It’s not worth the increased cost. The variable is the presser. It’s a bit of an art, like cooking.