how long does it take to level to 64?

[Silverbane]

I went to the Diadem as a Lvl 15 Botanist dressed in HQ gear gear, with +50% XP buff from the gear (earings, headpiece).
I spent the whole time harvesting Lvl 10 items from the nodes -- the XP from the nodes goes up as your level goes up.
So 40 minutes later, with no gear changes an no need to stop for repair, I was at Botonist Lvl 32.

I'll need to change gear at Levels 60, 70, and 80 if I continue.

Update: I returned to the Diadem as a Lvl 15 Miner, and this time used a company-issued Survival Manual.
Mining level 10 items on the nodes, I made 20 levels (to level 35) in 30 minutes.
Shortly thereafter, the Survival Manual hit its 500K XP limit.