I use the 'Guide' hard button (looks like an open book) just above and to the right of the scroll wheel for cancel, clear or go back depending on the activity. Firm keys 1 to 5 are almost always used up with transport controls. So for me they are not an option. There will certainly be a lot of differing opinions on this subject. The main idea is to be as consistent as possible throughout your design.

The home button will take me back to the main activities page and the power button will toggle the power on/off for the device I am currently on. A press-and-hold of the power button will shut the system down... much like that of a laptop computer. I created a very obvious soft button on my activities page to return back to the previous activity I was in... see image below.

IMHO I find that the guide button is a poor use of a hard key. The one thing that the Marantz remotes (at least in their previous models... RC5400, RC9500) did right was change this button to a cancel button... a much more frequently used button for most devices. At least they included this button on the 9800. This is the one thing I wish Philips would change. Perhaps this is a more common function in Europe.

Is there any chance of purchasing the ‘return’ hard button in order to replace the ‘guide’ button on the 9600? I am assuming that they are the same size and would not be much more difficult to replace than opening the remote to replace the battery.