I've killed and eaten old mule deer taken before the rut and they aren't bad although I do taste more of a sage flavor. The whitetails where I hunt in TN are largely stick eaters (no ag crops around but we get some good mast crops every few years) and they taste good to me but maybe because that's what I'm used to. The bucks I've killed in IL post rut were not noticeably better than the buck here even though they came from the largest corn crop there may be. Oddly some of the best whitetail bucks I've eaten were ones I've killed in South Dakota during the rut and their diet was largely grass-no ag in the areas I hunted.
The best game I've eaten was a caribou bull I shot in Quebec pre rut but most every one I have talked to says rutting caribou are terrible to eat.
