Is this more than a graphical wrapper around the 'createinstallmedia' tool tucked inside the installer app package?

https://support.apple.com/en-us/HT201372

That's all it appears to be, at least according to strings(1).

What about that DetectX software on this site, anyone use that?

call me paranoiac but I would be worried if thre was a spyware into this, I don't see no sources I can compile or inspect!