Pre-rut anything is generally good, but other factors, as said, are involved.. I prefer mule deer meat to elk, myself. Haven't eaten much of either, tho.
I try to avoid killing for meat in active rut. Except female critters. Some folks can't seem to manage to kill anything male that isn't rut crazed tho......
Meat can, in any species, be the good, the bad, and the ugly, depending on a number of factors.
I don't want to talk about my last two, too-close-to-the-rut moose (one on each side of the rut - dog ate well tho).....We ate too, but it definately wasn't "good". Closer to the "I killed it, gotta choke it down, with the living hell spiced out of it".
On the flip side, one of the best moose I've eaten came in all wall eyed and blowing snot, neck swollen, pink tongued, stomach empty....Sept 13, well before active rut starts around the 25th.. But then he had effed up antlers on one side - probably either testicular damage or horn bud damage, so that may have had something to do with his pre-rut rutting status.
The last time I'd seen him was 4 years before, at which time he had a fair, but sub-legal (if matched) antler on one side, and about a 20 inch spike on the other. Said spike actually made him legal (slot regs) , but he didn't show me the spike side until he was stepping into the brush, too late to shoot. When I killed him, on the damaged side, all he had for brow tine was, a 3 inch diameter , 5 inch long lump of antler material hanging down where that brow tine should have been, and negligible 1/4" points on the palm. Had he had antlers balance to the good side, he would have had a 59" spread. As it was, he went about 51" IIRC.
Two 2 or 3 year old bull moose that I have killed were "tangy" - and they were both killed several weeks before the rut. I have a theory, perhaps unfounded, that some "teenage" bulls, like humans, have their hormones AFU, until they get a little older.
I seem to keep killing culls.....but most of them eat fine.
All this is to point out that when you pull the trigger, you take your chances. Every critter is an individual. Work the odds.