Hello,
What is not stated in this thread is that these apps are not currently live and in beta
status.
The Amahi one-click app makes use the the Amahi Netboot (PXE) technology. You can basically install it on your HDA and network boot from your clients to the HDA to access this software. When you make backups, there is a preconfigured share that all the files will be stored in on the HDA. By purchasing the Amahi version, you gain the setup as mentioned above and don't have to burn CDs each time the app is updated.
http://wiki.amahi.org/index.php/Amahi_Netboot_for_noobs
There are other apps such as Clonezilla, Parted Magic, gParted, and Damns Small Linux that have been packaged for Amahi as well. They all work the same way via Amahi Netboot.
These apps are provided for convenience, i.e. minimal or no configuration needed. We know you can download the ISO, burn the CD, and use it for free. The reason we apply convenience fees to apps often is due to the development needed to make it Amahi compatible. Some take quite a bit of time and testing.
As with most Amahi apps, you can use our version or you can manually install yourself. It's your choice.
Hope that clarifies things for everyone.