New York Post Composite If your hair routine has ever pushed you to the brink of a questionable late-night decision, consider this your sign to upgrade it. Amazon just knocked $150 off the Dyson Airwrap Multi-Styler and Dryer during its Summer Beauty Event , and it’s the price drop that made me applaud (cue the handclap emojis) mid-scroll. To be honest, this is the type of product that usually lingers in your cart while you debate whether it’s a practical upgrade or an unnecessary splurge. But right now, the decision feels a little easier. Dyson Airwrap Multi-Styler and Dryer Amazon I’ve tested practically every blow dryer under the sun — drugstore staples, salon favorites and the hardcore ones that sound like they’re about to take off — and the Dyson Airwrap holds a signature status for a reason. It’s one of the few tools that consistently delivers that polished, put-together look without requiring a full arm workout or professional-level skill.…