These models are quantized INT8(both of simple and convrot) for ComfyUI 0.27.0 or later. They are fast in Ampere(RTX30x0)/Ada Lovelace(RTX40x0)/Blackwell(RTX50x0).
They used Starnodes Model Converter, made by Starnodes2024, quantized from BF16 models
https://github.com/Starnodes2024/comfyui-starnodes-modelconverter
Or quant_int8_convrot.py of ComfyUI's official ComfyUI model tools
https://github.com/Comfy-Org/comfy-model-tools