There's a plenty of programs that can unpack .7z files, and this format produces smaller files than than .zip or .gz. If you're too paranoid to use 7-Zip just because there's no checksum available on their HTTP only website (lol), just get another program that can read them...
Avell A70 MOB: Core i7-11800H, GeForce RTX 3060, 16 GB DDR4-3200, Windows 11 (Insider Preview)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)
ASRock Z97M OC Formula: Pentium G3258, GeForce GT 440, 16 GB DDR3-1600, Windows 10 (22H2)
