If you use the instructions (whether Benjamin & Medwin, Bellman, or Vesubio - they are all essentially the same design), you will wind up with a poor, sour, extraction that occurs over a long period of time. Trust me, I have a lot of experience with these! I used these for years before I even started roasting coffee. The keys to getting a decent beverage are:
1) Begin with cold water, I have tried to cheat with hot water out of a kettle and it does not work...
2) Load the basket with a medium or medium-fine grind of coffee. If it is too fine you will get horrible channeling. Many people try to put espresso grind in these things and wind up with a lousy extraction - the coffee mass is too large and the pressure too variable to get a good extraction with super fine grinds. Do not tamp it down, but make sure it is full (or that you use the spacer if it has one for the amount you are using).
3) Open the steam wand, close the coffee valve, and put it on the (medium-high) heat. It will take about 10 minutes (for a full load) to heat up until the point where you have significant steam being generated (but it is not boiling). At this point open the coffee valve, then close the steam valve. The steam pressure will drive the hot water through the coffee at a reasonable clip and effect a fairly decent extraction over about 30-40 seconds. If you do it the way they suggest, the water is not really hot when pressure begins to force it through the coffee. You will not enjoy that, believe me! Others suggest having both valves closed while heating. The problem with that is that you build up so much pressure that when you open the coffee valve, the coffee mass gets fractured with the sudden release of pressure.
4) [if steaming milk] Close the coffee valve when you have enough coffee and/or it is extracted to the degree you want. Wait 30 seconds or so for pressure to rebuild and then steam your milk. Otherwise just leave the valve open and allow to cool.
