After using iGo 8 for several years, I switched to Primo last week and the best feature so far is its ability to survive sleep. I have a Mio C320 and when you wake the device from sleep, iGo used to show up and then reboot. That took a while every time you started the device. iGo was still a very responsive software. But the restart was annoying.
In Primo, they seem to have "fixed" that. When you wake the device, Primo is there for you! This makes my Mio work just like a Garmin or Tomtom.
Just thought I'll share it with others in case someone is waiting on the upgrade for lack of features. This feature alone is worth the upgrade for me.