Fraud screening, Riskified vs Signifyd vs Sift, what’s the right stack?

At luxury watch AOV, fraud is existential. A single $50k chargeback wipes the margin on 200 honest orders. The three serious tools:

• Riskified, chargeback guarantee model. They review the order, give you a green/red decision, and if they approved and you got a chargeback, they pay it. Pricing: ~0.6-1.2% of transaction (negotiable at luxury AOV; bigger dealers pay 0.4%). My default for $1M+ GMV luxury dealers.
• Signifyd, identical model, often better in EU (more local fraud-pattern data). Often quoted slightly cheaper than Riskified. Worth pricing both.
• Sift, rules engine, no chargeback guarantee. You build the rules (velocity, IP reputation, BIN-AVS-CVV combinations, shipping forwarder detection). Cheaper (~$0.10-0.30 per order) but you eat all chargebacks. Best layered under Riskified for pre-screening before paying review fees.

The pattern I ship: Sift pre-screen (auto-decline obvious fraud, free of fees) → Riskified review (paid review on the survivors) → manual review queue for orders above $25k (you eyeball the photos, ID, and source-of-funds question for high-AOV). Magento integration is via official extensions for all three. Set the manual-review threshold at $25k for AOV under $10k average, $50k for higher.

Chargeback insurance via your acquirer (Stripe Radar+, Adyen RevenueProtect) is a weaker fallback, they screen for general fraud, not luxury-watch-specific patterns.