### Lets see:

**Mega Metagross:** Tough Claws boosts direct hits by 33%, or 1/3. Bullet Punch has a power of 40, plus STAB, 60. 60/3 is 20. 60+20 is 80. **Mega Metagross' Bullet Punch has a power of 80.**

**Mega Scizor:** Technician boosts moves under 40 power by 50%, or 1/2. Bullet Punch has a power of 40, plus Stab, 60, plus Technician, 90. **Mega Scizor's Bullet Punch has a power of 90.**

**Mega Lucario:** Adaptability boosts STAB by 2, not 1.5. 40x2 is 80. **Mega Lucario's Bullet Punch has a power of 80.**

### In conclusion, Mega Scizor's Bullet Punch hits the hardest, at a power of 90.