The basics of Ashby's mods to the 190 El Grande are: 25-degree edge angle, Tanto tip, and narrowing the blade taper angle front to back slightly so it's 1" wide at the back. Ed has written a basic how-to about this, with photos, and if you want to see it you can write T.J. at TBM and insist he publish it asap.
As for me -- I'm frankly growing frustrated with a broadhead manufacturer who the world's expert on arrow lethality says has almost got it right ... yet who refuses to make the minor modifications (including most importantly providing an out-of-box product that the average hunter can sharpen without a Ph.D. in engineering). They won't even answer my emails and phone calls on the subject, and all I'm trying to do is help them provide the best broadhead in the world. Go figure ...
As I've said before, if I were a hungry bowhunting entrepreneur, or a broadhead manufacturer already in business, I'd study what Ashby has to say, study what we have to say is right and wrong with the Grizzly (including really uneven weights out of the package, which, in my limited experience, have never once been as heavy as advertised), and offer the perfect killing machine in a broadhead, get rich quick from grateful customers, retire and go hunting! Geeze, it ain't rocket science (although, according to my personal moral code, killing fast and clean is a far superior moral concern than going to Mars and back). If I were younger, smarter, and richer, I'd do it myself. Sure wish one of you would ... dave