Keep this list handy when looking for the right headset. When buying telephone headsets, it definitely pays to shop around. Even if you are only buying one, you can generally avoid having to pay list price. If it is, look for a headset that will not work outside the room. This reduces the need to have multiple headsets or amplifiers on hand in case of breakdown.
Comfort is definitely in the head of the wearer.
If your office is noisy, make sure to test headsets in a similar environment. Make sure they come with at least a six-month warranty. If possible, use phones that have a headset jack and headsets that can use them. It beats having to lift and lower the phone handset to answer and end a call. If you need to do so though, check for a vendor that offers a lever that resolves the annoying problem of having to find a space to rest the handset during the conversation.