I had my truck for 6 years and I never absolutely needed 4x4. "Why?" you may ask. It's because: driving skills>4x4. If 4x4 was necessary, it wouldn't be optional. For mild off-roading, you should be fine.
I drive off-road for work a lot. All of our trucks are 4x4. The only time I've ever used it was when I did something dumb.