Why is this free av moonsecure, a black av sheep?

Hi malware fighters,

We all know avast as a free av of choice, we know ClamWin as an additional non-resident av, most of us have MBAM as an anti-malware solution of choice (non-resident), some have in the cloud ImmunetProtect installed, but this one is controversial: http://www.moonsecure.com/
Moonsecure is open source based but the developer did not disclose the source code.
It is not heard from much and cannot it be used alonside avast?
I also did not get much reactions on MxOne, the mexican av solution for peripherals (USB, pendrive, etc. etc.), I use it on my USB sticks and am testing it, the user base is mainly Spanish (Mexican), Portuguese,

polonus