Personally, I don't like the rear being 1/4" higher than the front. I don't get a good clean cut with the deck set like that. I get a cleaner cut with the rear 1/8" higher.
@Tiger Small Engine said level all around. It's worth trying.
Think of it this way. Most push mowers can only be set to mow at level all around. Some people scoff at setting zero turn decks like that. Also, take a look at lawn tractors, the decks are usually set up level all around.
Play around with it. See which setup works best for your particular mower.