You can image across HALs, it is not supported by Microsoft and they definitely won't tell you how to do it. Dell manages to do it with their x-image, which is an image that major corporations will give to Dell when they have a large account with them. You can tell Dell what hardware you want the image to work on and it will do it. It takes forever for the pc to boot up for the first time as the x-image reboots several times while loading drivers, it uses a WinPE environment to do this.
The way we got around the image problem is to have a bootloader at first bootup that gives you 120 seconds to choose which HAL you wish to use. We have all 4 HALs as a choice upon first boot. If you choose the wrong HAL, it blue screens, you reboot and pick a different one. You then use sysprep too switch over to the normal boot.ini on first reboot so you don't still have that first four option choose everytime you bootup. Needless to say, our image works across non-acpi, acpi, single and multi processor acpi HALs. Good stuff.
The way we got around the image problem is to have a bootloader at first bootup that gives you 120 seconds to choose which HAL you wish to use. We have all 4 HALs as a choice upon first boot. If you choose the wrong HAL, it blue screens, you reboot and pick a different one. You then use sysprep too switch over to the normal boot.ini on first reboot so you don't still have that first four option choose everytime you bootup. Needless to say, our image works across non-acpi, acpi, single and multi processor acpi HALs. Good stuff.