My FIL bought me one for X-mas a couple years ago... not bike specific, Craftsman. I bought the allen wrench sockets that go on it and I printed out a table of suggested torque values. I use it, but I got along fine without one for many years.

I suggest getting one if you have:
carbon handlebars
carbon steer tube
carbon stem
carbon crank

Otherwise, your calibrated elbow from 80's bike shop work will be fine.