Margin Labs published a research paper titled The Lab that breaks down when embedded card issuing is worth building for a vertical SaaS platform and when chasing the interchange leaves you with a card nobody uses.

Margin Labs helps vertical SaaS platforms evaluate and capture embedded payments revenue. Most platforms know payments is an opportunity. Few have a clear picture of the economics, the model options, or what execution actually requires. We close that gap. Our work spans the full payments decision lifecycle: model evaluation, vendor landscape, ROI methodology, processor introductions, and implementation strategy. We've worked across the payments ecosystem for over a decade - processors, platforms, and the infrastructure in between.