Coinbase prediction markets is the most convenient regulated option for U.S. users already on Coinbase, but convenience is doing most of the work here. The product is real and regulated, but it trails Kalshi on exchange depth and Polymarket on market breadth and data access. The cash-out flow, the scheduled transfer window, and the absence of any API or historical data suggest a product built for occasional retail use rather than active trading. The insider-data breach and the earnings-call contract episode both point to trust risks that sit outside the prediction market itself but run through the same account layer. At 6.5/10, it earns its score by being accessible and regulated, not by being good at prediction markets specifically.