109 base Spe is a little trollish because it is a little under the preferred base 110, but you hit 348 Spe with a Timid nature + 252 EVs. This is enough to outspeed the musketeers, including Keldeo and a huge portion of the meta as you can see there
http://www.smogon.com/forums/threads/oras-speed-tiers-v2.3556631/.
I don't think that the Icy Rock is the most useful item on A-Ninetales. If you want to play offensively, 81 SpA is workable when paired with the right coverage.
Some nice calcs with Life Orb as item if you want to run this thing aggressively:
252 SpA Life Orb Ninetales Moonblast vs. 0 HP / 0 SpD Keldeo: 322-382 (99.6 - 118.2%) -- 93.8% chance to OHKO
252 SpA Life Orb Ninetales Moonblast vs. 0 HP / 0 SpD Terrakion: 322-382 (99.6 - 118.2%) -- 93.8% chance to OHKO
252 SpA Life Orb Ninetales Moonblast vs. 0 HP / 0- SpD Kingdra: 343-406 (118.6 - 140.4%) -- guaranteed OHKO
252 SpA Life Orb Ninetales Moonblast vs. 0 HP / 0 SpD Mega Tyranitar in Sand: 172-203 (50.4 - 59.5%) -- guaranteed 2HKO
252 SpA Life Orb Ninetales Freeze-Dry vs. 248 HP / 0 SpD Rotom-W: 205-244 (67.6 - 80.5%) -- guaranteed 2HKO after hail damage and Leftovers recovery
252 SpA Life Orb Ninetales Freeze-Dry vs. 252 HP / 4 SpD Quagsire: 614-723 (155.8 - 183.5%) -- guaranteed OHKO
252 SpA Life Orb Ninetales Freeze-Dry vs. 252 HP / 176 SpD Mega Slowbro: 213-252 (54 - 63.9%) -- guaranteed 2HKO after hail damage
252 SpA Life Orb Ninetales Freeze-Dry vs. 252 HP / 144+ SpD Gastrodon: 395-473 (92.7 - 111%) -- 62.5% chance to OHKO
252 SpA Life Orb Ninetales Freeze-Dry vs. 252 HP / 4 SpD Suicune: 195-229 (48.2 - 56.6%) -- 84.4% chance to 2HKO after hail damage and Leftovers recovery
Hail in OU means that Blizzard spam can be a thing i.e. on Starmie to net some KOs.