There's more items than what I usually find for treasure but some of them are BoA so once you loot it, you can never loot it again on your account. It also however changed the pace of leveling which many seemed to be concerned about - just thought I would share this little tid bit of information. Patch 8.0 seemed to have changed a lot of things, the scaling of ilvl, hp, etc. It let you pretty much skip all of Pandaria questing and get to 90 in a couple hours so you can hop over to WoD content, blast through that in a few hours, hit 100 and get to Legion. Prior to 7.3.5 they gave enough experience to get you from 85-90 in about a couple hours which was amazing because if you were leveling an alt through Pandaria again it was super helpful. In 7.3.5 the experience they gave seemed to have been nerfed significantly, they were giving around 5k experience each after 7.3.5 and now give around 30k+ (the optional treasure chest only gives like 15k experience though).
It netted me about a level once my rested experience left. For anyone has done the achievement for these or would collect them while leveling - they've increased the experience they give again, but it's only about 1/2 a quest to about 3 quests worth of experience with full heirlooms, warmode on and rested exp.