Mass XL out of Plaska Industries has made the most sense for us. It's all natural and the science of its content comes from 17 years of testing at major Texas universities . The price amounts to about $75 per buck and maximizes growth , produces dark antlers , and has our bucks out of velvet in late August. We start feeding April 1 and feed til end of July. We top dress 11 lbs of Mass XL to approx 200 lbs of ADM 18%.. The only detriment seems to be shipping costs and availability. It is better now that Mass XL ships in 5 gallon buckets but the product has limited production. For us we are producing better antlers than we ever did with the synthetic antler supplements.