I do and I love them.
I've had my Aftershokz Bluez for about 15 months or so now and use them when I ride alone. Mine are the bluetooth ones. When I'm approaching junctions/busy areas through town etc, I just hit the pause button on the headset so no music then. When I'm out on the open road I listen to music - not loudly, just as background. Something with a good beat will get me up hills
- and lets face it, I need all the help I can get, being a flatlander and all.
Mine were £85 in Summer 2014, well worth the money for me. I also use them for walking the dogs, doing the gardening etc. I can link them to my iPhone so can even field a phone call (go away, I'm riding my bike) if necessary. £40 is a total bargain.
Just to add, that I can hear my tyre noise on the road, while listening to music. They do not impair my all round hearing while wearing them. It's a bit like listening to the radio in the car, although I do pause at busy places, as I've said before. Sometimes I need to really concentrate on every bit of riding so I don't listen then.
I wouldn't dream of having 2 earbuds in my ears, while riding now. Nor would I dream of using those big 'cyberman' headphones while walking or riding. I only use my 'proper' headphones, indoors for playing guitar.