For MGAs and agencies under $25M DWP, a modern insurtech core (Socotra, Ledgebrook, EIS) at $250K-$1M/yr beats custom — you inherit rate-and-form tooling and NAIC reporting. Socotra or EIS pay off up to $250M DWP for carriers with standard P&C products. Guidewire and Duck Creek start to make sense above $500M DWP where the 24-month-plus implementation pain is offset by decades-long license discounts and ecosystem. Custom builds only win for embedded insurance, narrow-specialty (parametric, pet, legal), or MGA plays where the go-to-market differentiation is a proprietary rating and underwriting model — break-even vs Socotra lifetime cost is typically month 28-36 at $50M+ DWP with proprietary product IP. NAIC stat reporting and SERFF filing add $150K-$500K/yr regardless of stack choice.