I have a Gentex HGU-56/P. I like it a lot, it's comfy but it is pretty wide and it can restrict some of your space (though this mainly happens while climbing into the cabin and banging your head!) the main concern they had with these though was the little protection they offered around the ears - it's basically just a thin shell.
Other than that, I have had minimal problems with it and the factory ear phones/mic are very clear and I highly reccomend it to anyone.