In previous expansions, doing things like this would actually benefit you because you could get ahead of the crowd and into zones they couldn't get to yet. However in Legion, everyone can go everywhere. So there really is zero benefit from doing this other than getting to 110 a few minutes ahead of the others. Which still means jack all because you can't do heroic/mythic content by yourself.
It's on average 15 hours to level to 110 by mediocre levelers I know in beta. 15 hours. For people who can level quick, that will drop to around 10. What's the point of trying to rush that even more? I plan to have 3 toons to 110 (for profs) by day 2.
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You seem to be misinformed in some ways. The drops scale to your level, yes. But the ilvl of the drops still remains. All zones other than suramar cap at set ilvls. Suramar can't be done until the other 4 zones are and that is where the higher end gear drops. World quests, if I've heard correctly, drop comparable gear to suramar. So if you are saying you plan to hit 110 and do the first areas to get better gear, you will fall behind those that did the zones leveling and got to suramar.