I personally like a bullet that holds about 50% retention. I shot a ton on elk with these type bullets and I feel you get a quicker better kill than with a high retention. For what we hunt in US there really isn't a huge need for high retention bullets. Also price for high retention bullets is usually more.
That's my opinion but it just that. I don't think anyone can say one kills better than the other between high retention and fragmenting bullets. In different situations each has an advantage over the other.
If you are able to produce both types I think you should and let the market decide. I see a huge advantage if you have a load work up for your high retention bullets and a guys decides for a particular hunt wants more frangible type, you can just buy the other type and not have to work up another load. I think that would be a great option to have.
That is a great way of looking at it.
What should we name the two Hammer Hunter lines? Lets hear it. This could be fun. We'll see, may have to start a new thread to find good names.