We've used them in the past, they are a nice product but just like anything else another "tool" to help get the job done. Ultimately when making cuts in tubing and getting a tight joint the final fit will come down to your measurements anyway and the accuracy and style of tool to make the notch.
I get better results with an old paper towel tube, than I do with $250 worth of pipemaster tools.
Try it for one joint! And when your are done, square the end, and use it again.
Rip a roll towel tube (or toilet paper) along the seam. Roll it around the tube diameter you want. Slap a piece of tape to hold the diameter. Start trimming it to fit the joint, and mark a paralllel line on the top of the tube for reference, and on the paper tube. Once the tube fits well, then transfer it to the CM tube. Leave it +.050 or so for final fit.
Problem with Pipemaster is the rods dont conform well with tight angles.
Pretty sad when "garbage" works better than an expensive product.