I would just like to say that there are slightly more efficient EV spreads out there. Like 252 HP / 0 Def / 96 SpD Careful nature, which has the better overall defenses as your spread but with 104 EVs left over.
This is a set I always use on the 'top.
Hitmontop: 50/95/95/35/110/70
Hitmontop @Assault Vest
Nature: Careful (+SDef,-SPAtk)
EVs: 58 Atk/100 HP/100 Def/252+ SPDEF
- Rapid Spin
- Brick Break
- Theif
- Earthquake
Most people look at this set and think - WTF? This is an assault vest set. Rapid Spin is used to clear spikes, web, and rocks. Brick Break is used to break screens set by Espeon/Carbink. Theif will take away the sash, or leftovers from a defensive pokemon. Earthquake is there for the damage.
252 SpA Espeon Psychic vs. 100 HP / 252+ SpD Assault Vest Hitmontop: 134-158 (50.3 - 59.3%) -- guaranteed 2HKO
252+ SpA Florges Moonblast vs. 100 HP / 252+ SpD Assault Vest Hitmontop: 138-164 (51.8 - 61.6%) -- guaranteed 2HKO
252+ Atk Heracross Close Combat vs. 100 HP / 100 Def Hitmontop: 196-232 (73.6 - 87.2%) -- guaranteed 2HKO after Leftovers recovery
252 SpA Mega Charizard Y Air Slash vs. 100 HP / 252+ SpD Assault Vest Hitmontop: 132-156 (49.6 - 58.6%) -- 98.4% chance to 2HKO
252 SpA Togekiss Dazzling Gleam vs. 100 HP / 252+ SpD Assault Vest Hitmontop: 114-134 (42.8 - 50.3%) -- 2% chance to 2HKO
252 SpA Espeon Psychic vs. 252 HP / 96+ SpD Assault Vest Hitmontop: 152-180 (50 - 59.2%) -- guaranteed 2HKO
252+ Atk Heracross Close Combat vs. 252 HP / 0 Def Hitmontop: 219-258 (72 - 84.8%) -- guaranteed 2HKO
I would recommend something like 252 HP / 56 Atk / 24 Def / 176 SpD with a Careful nature.
Also I agree with the people saying to replace brick break. Being in against an Espeon or Deoxys-S is just not a good matchup to break screens. Run Close Combat, it's so much more powerful.