CPUstress image: Power button behavior (opinions please)

Hello everyone who uses CPUstress image in UBCD for stress testing.

I'm planning to build a next version of this image, with an updated Linux kernel and stress programs. For now, I face a small question about the power button behavior in it. Currently, pressing power button in CPUstress does nothing. It won't do software shutdown or hard shutdown either. I would like to fix it in the next version, but I'm not sure which behavior is better. So I would like to see people who does use these stress tools to give me some opinions.

Do you prefer software shutdown or hard shutdown when you press the power button in CPUstress?

Hard shutdown:
- Kernel is slightly smaller. No need to compile ACPI power button driver or acpid.
- Same behavior as in original, CPUstress image from Icecube.
- Con: I'm not sure if pressing power button during middle of mprime test is good for CPU... (There won't be hard disk damage, though.)

Software shutdown:
- Will need ACPI power button driver, acpid, and configuration.
- Will be same as typing poweroff in the shell.

Or, keep the current behavior (do nothing).

Opinions, please.