For me the steel bumper has a perpose.
1. I found one that increases my approach angle quite a bit. It actually makes a huge difference in this are
2. When I do a trail and I see the turn is to sharp and my nose is going to touch a branch or small tree I do not back up and take another line.....I simply push through it
3. I also have those bars sitting over the headlamps. This helps me to see exactly where the corner of my bumper is and also exactly how close I am to anything in front of me. This helped me to finish 38th overall out of 180 entrants in the Jamboree challange last year
4. It looks cool
Pretty much what Michael said...
When I first got my Patrol, was a little bit of a learning experience in terms of driving. ie: It's like driving a battleship. Was disconcerting, as I was not particularly used to driving a vehicle of that size. My Patrol did have a nudge bar on, with corner pieces and front bar, which helped considerably, as the bars over the headlights do allow you to know exactly where the corners are, and the front part of the bar also gives you a very good indication of exactly how far you are away from an object in front. Made it a little easier to adapt to the sheer size of the vehicle and fit into parking spots designed for lesser vehicles... But the nudge-bar really messed with my approach angles. Now have a BZT replacement bumper which has improved my approach angle considerably. And it also looks ueber awesome. It gives the vehicle a much more "aggressive" look. It means taxis and similar actually wait their turn at 4-way stops...
They also offer quite a bit more protection than the standard bumper. ie: I had an incident just before river trip last year where an X-Trail decided to change lanes whilst I was next to him. I slammed on brakes, but my front bumper did touch his back bumper. I got home and buffed the scratch out. He had to put his bumper in his boot. I assume it would have been quite a bit different should I still have had the original bumper.