Do you have a market that will pay you a premium for calves specifically with Black Hereford genetics? If so, then it's probably worthwhile to give it a try as long as it doesn't cost more than it pays. If not, then go get yourself a good Hereford or Simmi/Angus bull. You'll be glad you did.
Sad to say, but the Black Hereford Association, in it's current state, is little more than a pyramid scheme - you may not have to pay part of your income back up the line, but it's similar in that you have to buy your stock from the small group already there, and then you have to find a new group to market to. If they allowed you an opportunity to breed up from registered Hereford and registered Angus genetics of your own choosing, it might have a chance to go somewhere, but as long as they will only register cattle that both parents come from their very small established genetic base, I just don't see a lot of future there. If you just want black baldies, you can raise better ones cheaper without the Black Hereford Association. Just my opinion, but it comes from a little research and from watching a couple of friends and neighbors trying them - neither of them stayed with them very long.