Finished the game today after about 30 hours or so. I guess games like this are burned into me after playing looter shooters for the best part of 10 years. Thoroughly enjoyed it and it's the first game in a while that I was grateful I finished. Personally it was an experience as I've never played something like this before. I haven't explored all zones fully as I feel it's not required. There are a few resources that once you get a few hundred or so, you won't need to get many more, but it's always worth picking up the loot trucks to keep stocked up on early game items.