Are synthetic makeup brushes as good as natural-hair brushes?

For modern formulas, yes. Across the reviewers we read, synthetic taklon-style bristles are now preferred for liquid, cream, and even many powder products because they don't absorb product, they're easier to clean, and they're cruelty-free. Natural hair still has a small following for loose powder blending, but every top-rated set in this roundup is synthetic.