OK, so you don't like Bosch dishwashers? For goodness sake, DO NOT INSTALL THEM! Live up to your high moral and ethical code.
You are, though, absolutely correct. Friends of mine are appliance engineers and they'll be the first to tell you that today's appliances will not last as long as the ones made 20 years ago. I wouldn't say they are disposable, but I'll be happy if I get 10 years out of our relatively new appliances. Two years out of the GE dishwasher was a bit annoying however.
Avoid cross threading, well of course. Any kind of plastic fitting, particularly if you have a metal fitting attached to it, will easily cross thread if you are not careful. That's why Bosch mentioned it. Why, just the other day a neighbor called me for the very same situation. They had attempted to self install a bidet toilet seat attachment (please, don't ask...) and the metal valve assembly that screws on the bottom of the Kohler valve assembly cross threaded. Common issue I suppose. I asked them to get an entirely new Kohler flush valve. It was $16 for the OEM valve assembly. I carefully threaded it on w/o cross threading. Took me 20 minutes to install the valve, install the bidet valve, and clean up.
You will not be able to access the back of the Bosch 800 by "tipping it forward" you have to slide it out, don't care what manual you have or what it says; unless you have exceeding long very thin arms, can work blindly, you won't be able to reach the back. You have to make the water connection prior to physical installation. Tipping it will not cause death; the thing doesn't weigh all that much. It's not a range with cast iron grates on top, or a refrigerator which weighs hundreds of pounds. You have to also make the electrical connection via proprietary plug, also in the back of the unit. No getting around it. Find another brand to install, and if someone calls you on it recommend another contractor to install.
My refrigerator's water connections are also hidden. No way to access them unless you slide the thing out. There's hundreds of push-fit PEX connections in my home and I suppose any of them could leak someday; and they are all buried in walls. All of that can leak. I'm satisfied my fittings on the Bosch are solid. Of course they are. I did it!
Maybe if you don't like these things, being a plumber is the wrong line of work.
