Been playing Rage on and off for about 15 - 16 hours saved play time (probably more when you consider deaths and reloading from a checkpoint loses registered play time), scouring everything, exploring, looking for secrets, collecting as much as I can and just enjoying taking my time with the game. I'm at
Spoiler the Dead City now for the second time.
Really enjoying the game the more I play it. Was a little disappointed at first, though.
Haven't tried the multiplayer yet, so cannot comment on that. I would like to get all PS3 trophies so will be playing through the SP on Nightmare.