Which PSP can handle heavy volumes well without issues?

Considering a new PSP for high-volume trading, especially in highly volatile markets like crypto, or during news releases with heavy spikes.\n\nPreviously, I encountered issues with my old PSP having latency problems when facing many simultaneous orders. Sometimes, there were unreasonable transaction failures, which means I missed quite a few critical moments and lost many opportunities. Anyone with experience with a PSP that can handle such volumes well, especially regarding processing stability and payouts, or even a straightforward onboarding process, please share.\n\nI understand that fees are important, but for now, I'm prioritizing reliability and performance. It would be great if the name isn't one of the Big-4 that tends to be restrictive or has overly complex KYC.