The bending-beam torque wrench is the most reliable design but is generally subject to parallactic reading error (which means the reading appears to change as
the operator's position changes). The dial torque wrench design is, in essence, a bending-beam wrench with a dial indicator to measure the beam deflection,
but the dial gage is itself subject to a small amount of parallactic reading error.
The clicker and break-over torque wrench designs do away with the bending beam but rely on what amounts to a spring-loaded catch that stays latched until
the applied force overcomes the spring loading. No parallax, but very sensitive to variations in friction in the latch. The usual clicker torque wrench
design is also subject to mis-setting, especially in the models having several setting scales for different measurement units.
Digital torque wrenches usually rely on strain gauges to measure the deflection of a bending-beam. No parallax, and no friction variations to cause errors
but being electronic, depend on circuitry and batteries.
Finally, there's the torque adapter, which is a short torsion bar with a digital strain gauge gauge and display. A very handy tool, but the at-torque light
or beep is very easy to miss.
My go-to torque wrenches are primarily clicker models, and even the el-cheapo models from Taiwan have worked well for me. I also use bending-beam wrenches
when it's possible to get the measurement scale and my eyes in the look straight down on the scale position.
Bottom line, you should pick something that meets your needs. It sounds to me like an inexpensive 3/8 inch drive clicker from one of the fast-food auto supply
chains (or Harbor Freight / Northern Tool) would suit your needs, but the torque adapter might suit you better. I'm attaching a link to Harbor Freight's
torque adapter as a representative example.
If you do go with a clicker, I'll STRONGLY recommend that you cycle the mechanism five times (to distribute the lubricant within the mechanism) before doing any
for-real torquing.
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