Quality - There's a few things that Workshop Publishing plans have going for them. First is the attention to detail and quality. I've met and have become friends with the author Doug Walsh. Doug is very meticulous about what he does. He's surely not a Johnny come lately, in fact he sees them come and go. His experience with this tool spans decades and his knowledge is deep. Most of his knowledge is from his own R & D and experience as a user.

Low Volume - A very important feature of the machine is its low volume vacuum chamber. Why is that important? SPEED -  The faster you form the part after its maximum heat tolerance the more detailed part you will get. That may not be important with some plastics but the thicker and better plastics used to build multi part objects require higher performance. HIPS forms very easy, one of the easiest plastics to form most commonly formed, but when you get into heavier ABS for example, speed is your friend.

Platen - The platen is the plate in which the forms sit on to be copied. This is where the volume is pared down to a very small chamber. Simplified, it amounts to two sheets of metal with a thin screen between them to make this thin chamber that allows air pressure to be sucked out quickly.  Hot plastic makes a seal over the whole plate pulling the plastic around the mold through tiny holes on the top plate. The holes are very small but very effective. The holes are barely conspicuous which leaves the margins usable as flanges

Permanent Seal - The platen has radius edges in which allows hot plastic to form a seal for the vacuum to pull air pressure from the chamber while pulling the plastic around the mold. This is built in feature never has to be replaced making this machine unique to others.