This is only my opinion...
But the truth is the trucks need to be SOA (which also means usually 35" tires or larger) and correct the diesel is loud. Nothing crazy, not much louder than a Dodge pickup but they overall are loud and big. It takes IMO maybe a kind of a youthful spirit or a little of a toughness to really have and love them and to daily drive or drive them often or use as your sole vehicle. Also a lot of us are getting older, starting to get families etc, and it works for a little while and they sure are awesome but it is sort of like driving a Ferrari all the time, they are killer but everywhere you go there is a huge (and in this case really loud) expedition vehicle that is a real eye turner. I absolutely loved mine and found that for DDer I would go on and off, drive it straight for anywhere from three weeks straight to a month or three. But I also always kept my Saab as a DDer and sometimes it was nice to just drive the Saab, it was the only way I kept my sanity with it. I didn't always want to be "that guy." It also begins to where you down, I'm usually a pretty outgoing guy but you can only talk about your truck so much because everyone wants to talk to you about it, all the time!
At the same time, a lot of us that have built or purchases one expected/panned to use as our sole vehicle and with little maintenance issues from small things that are left over from a custom swap, or again little regular maintenance issues that are more common with a larger expedition vehicle. It can wear you down, particularly when you have little time or patience or ability. When I sold mine, there were a lot of little things that had to be repaired. To insure a happy owner I did them all, e-brake cable adjust, some electrical and other little things, things that had rattled loose, horn etc etc. So I spent about two days doing all of this stuff. When I sold it it was so great, sort of like when you fix up a house to sell it, you wonder why you never did it. But these are the things that build up, and do unfortunately wear you down. And that is the nature of a custom vehicle like this unless you took *all* steps to prevent it from the get-go (I took about 90-95% of them). Also like a Ferrari it sort of becomes the car that people know you by, sort of like Magnum or something like that. So it is cool but also nice to escape a little...
Because of the nature of the engine, because they are really deep, usually the trucks need to be tall to have the axle not hit the engine. So to be proportional you have to run 35" tires (or larger) which are also very big especially by expedition standards. 35's are stock on H2s so they are not "huge." And with reasonable power (like that of a 4BT) it is powered very well. But the amount of muscle the engine needs & uses to get going is noticeable. And the feel and drive of it, you usually feel like you are driving a pretty big/tough vehicle. There is only once where I felt like my truck was "small" and "traditional" and that was at Cruise Moab. All other times it felt huge. Also if I drove like an ************ for some reason of course I would instantly get back looks and negative/redneck assumptions. Unfortunately due to the size it also makes the truck feel a little "over the top" to some people who choose to drive them.
So all of this adds up. But the cool thing is: the standard trans ones usually get about 22 or higher MPG (I am shooting for 27mpg highwat) with tons of power to spare, and the autos about 18mpg bare min. It tows great, wheels great, etc etc). For a huge sprung over truck that would probably get 10-12mpg otherwise it is great. For me, it was also cool to be eco. With biodiesel my carbon footprint was way smaller than even a Prius - now that is cool...
Off road though, they are just amazing, solid as a rock, you do not need crazy gearing because they have so much grunt and I found them to be pretty light on the damage department surprisingly considering some of the stuff I was able to do. With lockers, decent gearing, I was able to wheel (and even outwheel) unbelievably well built trucks and buggies that were more setup than mine when you used a little precision and intelligence. The engine and its weight are very well balanced for Land Cruisers, particularly in decent traction situations... And the drive-it-home with all the stuff you arrived in factor, and get good mileage while you're at it...
So, for some people it doesn't work, for some people it works great, some people it works for X amount of time but then then they choose to move on.
I hope it helps... You can see what I am talking about with the photos I've attached. I chose to sell it but in favor of building one that is is a better (less rust, more DDer oriented) but also because I loved it.
I'll also post up Henry's truck (which Dave Gonz also owned, and sold). Truly amazing an amazing machine.
But an expensive Toy, particularly if you don't use it often and/or need a good DDer too...
For me though, cruiser-wise, it is the pinnacle and what I plan to keep/use as long as I am into cruisers... It also daily drives and expeditions very well. I personally think with its wheelsize (and if built well) it expeditions probably better than most smaller trucks as well. It does not scramble at all and 35 is about a perfect size from a technical wheeling perspective where it can roll or walk over just about anything. Hang with the big boys (to an extent) but still get around just great, hold a load awesome, and wheel with the small guys really well too. This said, I am building a small mini truck with 33s for DDer use, daily winter/disposable use (ie rust killing it over a few years won't be a big deal) and more of a normal truck. But will use both extensively I figure...
