Bose X
gijoe,
On IO540's advice, I bought a Bose X headset about six moths ago and have never looked back - strongly recommended!
With regard to buying second hand, I must make it clear that I have never used e-Bay. I tend to be suspicious of such things. I am always afraid I might be buying stolen goods.
However, any Bose headset should have its serial number registered with Bose, and if that Bose headset is under five years old, it should also still be under warranty.
The warranty is transferrable to a new owner by Bose, but only at the request of the existing owner.
It might be worthwhile getting the serial number before you buy the headset and checking with Bose whether the name of its registered owner is the same as that of the vendor. You can also check whether the headset is still within warranty and then ask the present owner if he/she would be prepared to transfer the warranty to you. If he/she refuses, then back off.
Broomstick.