I would definitely want the bumper to take the bulk of the damage in a collision like the ones above. Those can be replaced a lot easier (and cheaper) than trying to straighten the body or frame, or purchasing a new(er) truck. That is why it would be good to see how these types of bumper mods help (or hinder) when in an accident.
I am also curious about the winching. Since the winch is fully enclosed, do you have issues with getting the cable / rope recoiled, or is this a non-issue?
If your first statement is true, then you don't want an ARB (or any steel bumper!). The impact energy has to be dissipated somehow (remember Newton's 2nd Law, energy cannot be created or destroyed), and usually this will take the form of noise, heat, and crushed metal and plastic in the case of a collision. The whole point of a crush zone is to absorb that impact energy before it has a chance to reach the passenger compartment. Unibodies do this much better than body-on-frame, because they lack that stout steel frame which resists being deformed by that impact energy. So, in the case of body-on-frame, that energy has to do something, and that something is to keep moving until it encounters something of less resistance (like sheet metal, glass, or the driver's chest cavity). Let's not kid ourselves, if safety were the number one concern, we'd all be driving sedans or mini-vans. The one exception to this argument is mass, which I will get to.
Anyway, the ideal would be progressive impact absorption by all components standing between the point of impact and the passenger cell. That is what the "flimsy" factory Tupperware bumper is designed to do, absorb some of that energy by deforming, then passing the rest onto the next "crush zone" in the system, hopefully progressively dissipating enough energy that little or none of it actually reaches the passenger compartment and does harm to human beings. By putting this massive, immovable steel bar in front of your truck, you have just guaranteed that those impact forces must go elsewhere (as seen in those photos), and in most cases that direction will be toward the passenger compartment.
The one concession one could make would be mass. All things being equal, it is usually better to have more overall mass than the object you strike, but I think that is only really relevant in the "passenger-vehicle-versus-18-wheeler" type scenario.
All that said, I have had steel aftermarket bumpers on most of my trucks (including the 100 Series, though not currently). But the reason has never been safety, but more for impact protection from animal strikes (i.e. keeping my radiator intact) and a place to hold winches, lights, and recovery points.
As for winching from the enclosed bumper, never been an issue for me.
My $0.02,
