Always attempt to download from the Official Hasleo WinToUSB Page first. While they promote the latest version, it is the safest source for the software.
If you specifically need an older version like 6.0, use reputable software archives like Uptodown or TechSpot , which keep historical versions of installers.
Before extracting a .rar file, upload it to VirusTotal to scan it against dozens of antivirus engines.