I read somewhere you needed about 45 ft lbs of ke to pass through or effectively harvest any north american game. Me personally I like the most I can get, I just bought a commander from Ben on here and am looking at the numbers on it and they show 78 ft lbs but I dont know how they got that number on bowtechs website. I am currently shooting about 78 ft lbs with my darton. I would not think you should have any problems with harvesting any north american game, however I don't think you should loose that much ke with a black ice. Maybe you need to try some different weighted shafts till you get the ke up a little bit, thats what I did with the bow I have now, I found that at a certain point in going up on the weight of the shaft my ke started to dropthats where I stopped and built arrows to match that weight (using weight tubes). For my darton that weight that gave me the most ke was 440g, that # will be different with different bows. When the commander comes inI will do the same with that and let you know what the different weight shafts give me as far as ke if ya want.......