I've actually hit two deer this season. The first was at speed, and solidly struck the bumper and right headlight guard -- hard enough to throw the (now much thinner) deer carcass about 20 feet into the bush along the road. No damage, other than blood & fur all over the nose of the rig (and temporarily modifying my blood pressure and heartrate).
The second was a small deer, center hit at about 20mph -- had almost enough room to stop, but no room to swerve -- just above the winch mounting hole, but below the grill guard. Didn't kill the deer outright, but did no damage and left very little blood/hair on the front. I briefly considered flooring the pedal and testing escape velocities for deer, but there was oncoming traffic, and I doubted the local deputy would see the humour in the resulting excitement, especially if the deer bounced off my bumper and into an oncoming car.
Once the winch is mounted, there's very little that actually protrudes beyond the front of the bumper face. The winch body is bolted securely through the bumper face to the fairlead, and unless the bumper face, winch bolts, or winch body were to fail, there would be no damage. With the larger 12,000 and 15,000 winches, there's not a whole lot of clearance, but I actually prefer that to leaving it without a winch -- there's lots of free space for road debris to bound up and strike the radiator/cooler fins.
You can see on
this picture of Earthroamer that the grill guard sticks out further than the winch fairlead, and is mostly protected from direct front hits. I think that anything large (tall) enough (tree, wall, moose, etc) to do damage to the winch mount will mostly hit the upper bumper and grill guard first. Anything small/short enough to hit the winch fairlead isn't going to do a lot of damage, IMO -- except maybe driving over small boulders, in which case you're more likely to rip stuff off the underside, as opposed to dinging the winch hard enough to break it off the mounting bolts and push it into the cooler.
All in all, I'm very happy with the DOR bumper. Stung a little bit to pay that much for a bumper, but having seen two deer bounce off it, I made the right choice.
-jon-