I can't recommend this.... got one a few years ago, and it didn't work. I explained to DigiSync guy what it was doing (not doing), to me it clearly was a defective unit...... he stopped communicating with me, never resolved it. Still on the shelf, to me it's a brick. I later picked up a Vacuumate, a very expensive tool that works perfectly.... it will bite your wallet hard. You don't need anything that perfect......
I'd get either a Morgan Carbtune or set of vacuum gauges. Be sure to calibrate (or at least know the deviation on each) the vacuum gauges.