Almost immediately, and the gap widens the more you pay people. Mellow charges 3.5% to 5.5% of payout volume. At the top rate a $4,000 payout costs $220, which is 4.4 times the flat $50 Kleos charges, and a $7,000 payout costs $385, nearly eight times more. The crossover is around $900 per payout at 5.5%, or about $1,400 on the 3.5% introductory rate.
Currency conversion sits outside those fees on both sides, and it is worth comparing directly. When a payout changes currency, Kleos applies a spread capped at 3.5%, and that cap is written into your contract at signing rather than published somewhere we can change later. Mellow publishes a percentage of payout volume but no conversion rate, so their headline fee is checkable in advance and the conversion cost is not. With Kleos both numbers are known before you sign, which means even the worst case is something you can put in a budget.