>>2089127175/90/90/140/90/115
vs
70/75/80/135/80/135
Manectric is (marginally) weaker than Houndoom in EVERYTHING bar speed.
in case you don't get it:
Attack:
252 SpA Mega Houndoom Hidden Power Ice vs. 0 HP / 0 SpD Dragonite: 276-328 (85.4 - 101.5%) -- 12.5% chance to OHKO
252 SpA Mega Manectric Hidden Power Ice vs. 0 HP / 0 SpD Dragonite: 272-320 (84.2 - 99%) -- guaranteed 2HKO
Defense:
252+ Atk Dragonite Extreme Speed vs. 0 HP / 0 Def Mega Houndoom: 107-127 (36.7 - 43.6%) -- guaranteed 3HKO
252+ Atk Dragonite Extreme Speed vs. 0 HP / 4 Def Mega Manectric: 118-139 (41.9 - 49.4%) -- guaranteed 3HKO
-1 252+ Atk Dragonite Extreme Speed vs. 0 HP / 4 Def Mega Manectric: 79-93 (28.1 - 33%) -- guaranteed 4HKO
(This one depends on who switched in first that's why I posted both)
Manectric IS overall better than Houndoom and that's why it's OU. 135 Speed Volt Switch with Intimidate makes for an excellent pivot. But as a sweeper? Houndoom can opt for Sucker Punch, Flame Charge and Nasty Plot in its movepool. It is just better.