I've posted this before, but I think it bears repeating.
When I worked for Alan Johnson/Al-Anabi Racing, they were sponsored by (it changed yearly), Travers Tool Company, Snap-On, Matco, and if I recall correctly, Cornwell Tools, and I think Proto also, there were a lot of Proto tools around. There was a tool box (there were a lot of toolboxes there), with a whole buttload of torque wrenches in. Maybe 75 of them. Maybe more. Inch pound, foot pound, 1/4, 3/8, 1/2, fucking everything. I go to grab one, and a guy says, "check it against the torque load check chingus over on the wall.", which had a load meter with digital readout, you set the torque wrench to say, 82 ft lbs, go until it either beeps or clicks, and read the true foot pounds of torque. And I don't think any of them were right on, I know some of them were way off. Even the new ones weren't dead nuts.
I had always assumed that the bigger money, high end stuff, was the way to go, but it isn't necessarily so. If you don't have one of those load meters, or have access to one real close to where you are working on your stuff (as in checking it every time you use it), you really don't know for sure what you are clicking at.
Someone mentioned to me that the most consistent ones they checked were the beam type, they don't change much over time.
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