It is difficult to label either one as the best option for forex and CFD trading because traders have varied requirements for their strategies and investment goals. ECN/DMA/NDD accounts are perfect if you want tight spreads, direct market access, and zero interference from the broker. On the flip side, ECN accounts will charge a commission for trading, and there will be instances of partial order fills, requotes, and slippages. Market maker protocols using an automated dealing desk help minimize the risk of these occurrences, but the spreads will be higher, and there is a conflict of interest since the broker acts as the counterparty to its clients' orders. Ultimately, it depends on which protocol satisfies your trading requirements.