Reviewed: October 3, 2025

I tested Runway's Gen4 Turbo across 30+ prompts spanning every category from physics simulations to human avatars. What I found was a model that gets you results fast but asks you to accept some rough edges in return.

After weeks of testing, Gen4 Turbo scores 50.47/100 overall. That's middle-of-the-road territory. The model delivers impressive speed and handles certain tasks beautifully, but it stumbles on the fundamentals too often to recommend without reservations. If you need fast previsualization or rough drafts, it works. If you're after polished final assets, keep looking.

The Physics Problem

Gen4 Turbo's physics simulation is where things get messy. Scoring just 47/100, it's clear the model doesn't quite understand how the world works.

I tested a snowy blizzard scene. The prompt asked for large snowflakes with realistic tumbling motion and natural wind patterns. What I got was a surreal mix of flowing flakes and completely static ice crystals that looked more like hanging decorations than falling snow. The moving elements ignored the frozen ones entirely. No collisions, no interaction, nothing.

An anime-style inventor scene fared slightly better. The character lowered a brass boat into water, and I actually saw concentric ripples form. The physics looked believable for a moment. But then the sleeve physics broke. The fabric should have dragged naturally through the water. Instead, it clipped straight through the basin edge. The model got close but couldn't maintain the illusion.