For a solo founder processing 100-300 emails a day in 2026, the cheap-stack option (Gmail labels + Claude Pro at $20/month + a 5-line prompt template) recovers roughly 90% of the value of an $83/month premium stack (Superhuman AI + Shortwave Pro + Reclaim.ai Pro) at about 24% of the cost. The premium stack is worth its price under three conditions only — 2+ hours/day in email, keyboard-shortcut speed gain that pays back at the founder's hourly rate, and a documented bottleneck the cheap stack failed to solve after a two-week trial. Without all three, the founder is paying for an aesthetic, not measurable productivity.

Operators-register procurement piece. Cheap stack costs $20-27/month, premium stack ~$83/month, both pulled from vendor pricing pages on 28 Apr 2026. The 90-to-20-minute triage compression is grounded in published productivity-blogger benchmarks (Cal Newport, Tiago Forte, Khe Hy) — not Peter's personal measurement. Status set to Partial at publication because the supporting time-recovery figure (90+ minutes to ~20 minutes) is synthesized from external practitioner writing rather than a Peter-run benchmark; the cost math is verifiable on the cited pricing pages but the productivity claim needs a tracked-cohort replication to move to Holding. 45-day review: vendor pricing shift, Gmail filter/label changes, Superhuman or Shortwave shipping a price drop or feature gap-widener, native Gmail integration from a consumer-AI vendor.