Rob's suggestion is the perfect solution.
However, if you don't have the dollars to buy a test kit, the second best option is to go "Old School." Go to a shoot and ask as many guys as possible if you can shoot one of their arrows. When you find the one that flies like a laser-------THAT'S THE SPINE FOR YOU.
P.S. In regards to the question about how much meat those wonderfully beautiful Howard Hill bows of mine have made, well, let's just say that one one hunt alone, one of them put over 4,000 pounds of meat on the ground for the local Aborigines. We even packed out the tongue. Hot work, but rewarding. I have to have two full-size freezers to keep up with what they shoot.
They may be beautiful and look like city-slicker bows, but MAN can they shoot!