I have these in my kitchen already, too quiet for me, you can't tell if its running and if there's a problem like the wash arm got stuck until the end, you do have to really scrape the dishes well before placing inside, there is no food disposer, mashed potatos will clog the filter and drain hose, trust me, its happened, the impeller has been replaced twice on the top machine, their plastic and can chip easily, I do tend to favor the top because of ease of not bending down, but in 5 years thats the only issues, they do come with a 2 year warranty, and fixed both times while covered, never a problem since.
you must follow one rule, that's in the book....the drain hoses meet using a "Y" connector to the sink drain, make sure the hoses are elevated to the top of the counter, they didn't do this when mine was installed and when the top machine would drain, the water would backflo into the bottom machine, and flood the floor if you did not notice this was happening, been there!
I want to get one for my mother, may not be the best machine, but just so she doesn't have bend to load and unload would be a great help, even the single drawer units are helpful in these cases....