Not a big fan of Xurkitree. It screams Rampardos stat wise: Monstrous Attack, meh everything else. At least Xurk's Speed isn't complete trash. Getting Tail Glow is pretty ridiculous, though it isn't doing much against offense unless you run Scarf, which means you forfeit Tail Glow which is too good to pass up. Coverage wise, very meh but with that Special Attack it can dent many Pokemon that resist electric.
If Unaware got nerfed which is starting to not be true, Xurkitree demolishes stall after one Tail Glow Boost. Even if Unaware remains viable, Xurkitree is serious threat to Stall once Clefable is out of the picture. Quag just gets blown with Energy Ball which is bound to be a staple on Xurkitree due to the lack of options.
Even with Scarf, it's a bit slow and will get outspeed by fast megas. 83/71/71 defenses are bad. It gets destroyed by strong neutral hits and being an Electric type is bah providing not very useful resistances. Ground types not weak to grass probably pose the biggest threat to Xurkitree. They block Volt Switch forcing Choiced sets to switch and can tank your coverage moves. Nidoqueen comes to mind, easily tanking non boosted neutral hits and SE Hidden Power before dispatching it with Earth Power.