Professional appliances aren't strictly better, because they're rarely designed to be quiet. Your example:

>Sound pressure level: approximately 65 dB [presumably dBA]

That's much louder than domestic fridges. I would find it unacceptably annoying.

You don't need to go to anywhere near that price to get before you hit a sweet spot. For like $600 including tax one of the biggest retailers in the UK will sell you the most energy efficient fridge on the market with a 5 year guarantee. Like most products, you're reaching diminishing returns at a certain point and that seems to be it as far as I can tell.