I had two sets of limbs for my bow, 67 and 54# at my draw.
I have to admit that I shoot the 54# better and wound up wounding a kudu and spooking another when I had to let down with the heavier limbs.
The 54#'s did an number on an eland, impala, warthog and kudu, and IMO are perfectly adequate for anything over there except of course the big 5/6 and giraffe.
However, I would say you need to use a 2-bladed head with the lighter wts., I recommend the grizzly and learn to sharpen them well.