Like others said; it depends on the car maker and the car type.
I just got from a Renault Megane which had a TPMS broken off so the message was constantly on display that the sensor was not right. Coded it out of the ECU really easily. Also BMW, Benz, VAG (VW/SEAT/SKODA) and some others are know to work great for the most part. Can't be sure of all since I did not do all of them yet however.
Which brands are you working on mostly?