Our installer is written with Inno Setup and we are actually quite happy with it. Yet some customers keep asking for an MSI installer which they could more easily distribute
Its pretty easy to make a wrapper kit that automatically installs INNOSETUPper from MSI. For basic functionality (install/uninstall) this is enough. Most setuppers do not implement repair anyway.
create silent.inf script for INNO Setup (optional)
create install.bat that calls
myinnosetup.exe /silent /NOCANCEL /norestart /Components="xxx"
you can use /verysilent
you can load settings from silent.inf with /LOADINF="silent.inf"
create MSI setup file that calls install.bat ( with parameters if necessary)
deliver all 4 files to your customer and they can deploy your Inno setupper with SMS or ActiveDirectory and everyone is happy :)