That's weird, aren't they supposed to sound exactly the same? I know the Pro has some additional effects and it's more flexible when making a patch, but for a basic rhythm guitar sound with the onboard cab simulation like the one you have on your video there shouldn't be any differences.
I have a HD500 and there`s a huge difference between earlier firmware`s and a current one.
I`m guessing if all the initial reviews were done with a current firmware, that impressions would have been much much better.
Ability to switch input impedance (apparently done via hardware) has made quite the difference with my Alternative 8 pickups, and also some tonal changes done to amp models have made pod HD much better at achieving good high-gain tones.
To me, a Uberschall model alone (the one with "broken" presence) is worth it.