Personal opinion. You won't like them if you can hear with both ears well. I used to use a wireless headset that didn't seal out the extraneous background noises. I've have since given them up. The primary reason was, if you blank out the extraneous background noises by covering both ears, listening for subtle sounds is much easier.
Mark, it is my understanding that they are both about the same thing. Ie.: once you have the relative switch settings, volume, etc..., you'd have the same thing. At least that's what I was told, when I was looking to get a set. So then, it merely became a matter or pricing.
If you buy the Killer B's make sure you send your warranty card in by certified mail. If the mail loses it you have no warranty. Happen to me. You would think in this day and time a company with a web site would allow on line registration but they don't.