Mechanical single trigger - Pro-Sensitive only to pulls (insensitive to recoil level); Con-mechanically complex.

Inertia single trigger - Pro-Low complexity and tunable; Con-Sensitive to recoil level.

Double triggers - Pro-Mechanically simple, easy barrel selection, and one barrel redundancy; Con-require repositioning of trigger finger.

All three types survive (and thrive) because each has uses and devotees. If one type were truly best, then that is what we would all shoot.