On Windows, if MtoA isn’t already installed, then the /S flag will do a silent install:
MtoA-1.2.7.3-2016.exe /S
You can also specify an install location with the /D flag:
MtoA-1.2.7.1-2016.exe /S /D=C:\solidangle\mtoadeploy\2016-1.2.7.1
There is no silent install on OSX or Linux.
C:\solidangle\mtoadeploy\2016-1.2.7.1\uninstall.exe /S
or, if you want to keep the existing install around, you could do this:
reg DELETE HKCU\Software\Microsoft\Windows\CurrentVersion\Uninstall\MtoA2016 /f
After you delete that registry key, an MtoA install won’t detect an existing installation, so you get to keep the old install, and install a new version.