Nothing new, the old tried and true Harry Elburg Grizzlies are near as old as the old time Rothar Snuffers. If you are handy with a good mill file, the Grizzly is a very cost effective single bevel broadhead that will give you many miles of service. I've not hunted with an Abowyer, but they appear to make a good alternative that is near ready to go directly out of the package. STOS is due out this spring with their version of the modified Grizzly as well.
Not sure why so many speak of the single bevel as something new, it is far older than many of the regular heads used today.