What is best might depend on what you are looking for in the payment gateway.
You could consider looking into CoinGate. In CoinGate, we offer crypto payment processing services with several methods to set up cryptocurrency payments for any website or physical store. Options include payment buttons, web PoS application, API integration, and official plugins for the biggest e-commerce platforms. Our automated gateway handles crypto payments every step of the way, from creating an invoice to confirmation of payment to customer support.
We support 70+ cryptocurrencies, including BTC and LTC Lighting Network, and you can choose to keep crypto from the sales or convert it to EUR/USD immediately after payment is received from the shopper. Also, shoppers don't have to register on our platform to pay for your products/services.
You can check out our services here:
https://coingate.com/acceptWe are always up for a chat if you have any questions!