Interactive is your default governor. ondemand will make your user experience the slightest bit smoother, but in turn at a hefty cost of using your battery.
It is best to get an app that will add a zipalign if you want the same smooth results as ondemand, without the cost of battery life.
EDIT:
Currently testing the device between interactive and ondemand governors. I'm on a personal search to see which delivers ideal performance between the two at the advantage of battery life while using the phone.
From what I've observed so far is that ondemand can be a little more conservative in terms of battery life. This could be the fact it drops to the minimum Cpu speed much faster than interactive.