I tried the Koss infrared wireless headphones some time ago. They were very noisy, like a bad gassy tube. Unless some radical improvements have been made, you'd be better off with an AM radio.
I think you would do better sonically with a good headphone extension cord and "wired" headphones. Unfortunately, the headwize.com forums are currently not working. Otherwize that would be a good souce of information.
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