No. It's not. The Unimog is the most capable offroad truck every built. Not even the Rubicon can really compare (though it's as close as a mainstream vehicle has ever come).
That is a Pinzgauer. It's Swiss made ***ETA: it may be Austrian as you said***. It's IFS f/r portals with factory lockers and a great low range crawl ratio...somewhere over 100:1, probably closer to 200:1. However....it has ZERO flex. It also is very narrow.....bad combo. Is it very capable in stock form? Ya. Is it the "best" ever built. Resounding "NO".
I once had a guy and his buddy that both owned one come into the 4wd shop I was working at and I went out and looked at it b/c it was the first time I'd seen one. It was pretty cool to look at, but had major design problems for the trails around here. The gas tank was right under the rocker panel as were the driveshafts leaving them completely exposed and vulnerable.
They were bragging up a storm about how it was the most capable rig ever built and that it would go "anywhere". I just smiled and asked them to join us on a trail run to Highway to Hell that weekend. Long story short, they got to the first obstacle and said, "There's no way we're gonna go in there!".
I'd still like to wheel with them again, just to see more.....but just getting them to the first obstacle was an exercise in patience to begin with....and most of that was just rutted dirt roads with off cambers, some rocks and steep hill climb/descents.
Here's a pic of the first obstacle:
As for how they compare to a Mog....Mogs have gearing options that go all the way down to 2000:1 (not a typo....two thousand). Mogs use solid axles and have amazing flex and while they appear really tall (especially on factory 40" tires) they have a VERY low center of gravity and are extremely stable on offcambers. There are a lot more configurations of Mog than Pinz. They both can be had in diesel or gas engines.
As for comparing them to Jeeps/Rovers/Etc. ......they don't really compare. They are quite a bit different than a "normal" 4wd.