Hi,
I'm not really experienced on both products but I'm currently working on re/packaging tools to help my company choose one (or two). I think you can't compare Wise for Windows Installer and IS AdminStudio.
If you want to repackage setups, you should compare AdminStudio and Wise Package Studio.
At that right moment, I prefer using WPS, which I find easier to use and seems to have the same functions as AdminStudio. However, WPS is more expensive. I don't know yet about the quality of the support.
There are other tools like Lanovation Prism Pack and Chicago Soft Walls 4 Windows, but to me, the best, because they are complete, are IS and Wise products.
One last thing about Wise for Windows Installer. You should compare it to IS Developper. They both aim at helping you create setups, in the MSI format.
That's all for me.
Regards,
Jerome