A comments struck me.... The type of grass.
We do grass fed for our customers, some of which are big restaurants in the city (giving them a local market vs their out of country choice) Using our beef as specialty dinner, specially prepared. Anyways, not the point.
Grass fed beef should be on green lush grass, right? Not dry winter grasses, not unirrigated pastures, not hay. What we have found is that the fat is what flavors the meat. The fat on grass fed beef is slightly yellow, in comparison to strictly grain fed. When beef are on drier pastures, the coloring of the fat is not there. That leads us to believe the composition of the grass is the key.
Some people like that gamey taste that comes from green grass fed beef. Some people like the combo fed beef, still getting the health benefits from the grass fed, but almost eliminating the gameyness. Personally, I will pass on grass fed.