Ask, and ye shall receive.
http://replay.pokemonshowdown.com/mixandmega-429824087
Unfortunately, I did not save a replay of LaxLapras being very quickly swept by that same Genesect, but he can probably vouch for it being nuts, I think...
Anyways, I want to review some underutilized Pokémon while I'm here. I'll only start with a few this time.
Zoroark: I was pretty excited to use this in battle, and its potential did not disappoint me with an Absolite. Illusion only wears off as soon as you mega evolve, but that's enough time to fool the opponent and put them in a bad situation. Mixed offenses with the ability to both of them are great. Just keep him far away from Extreme Speed; Zoroark's incredibly frail.
Tornadus: My experience with a Salamancite set was incredibly disappointing. Return as a physical STAB does not make up for mediocre bulk and power, even after a Bulk Up. If you want to use him, though, Pidgeotite is the way to go. Focus Blast and Hurricane will both do some big damage....
Torterra: Actually, it's better than it seems, and surprised me with that. Aggronite turns Torterra into a more aggressive Ferrothorn. Synthesis is not the most reliable form of recovery, but it will suffice in most situations. The only other thing to really say about this is that it takes physical hits especially well, an might be able to run Venasaurite as another option to reduce its weaknesses of its base typing to more manageable levels.