They look mighty realistic, to be honest.
The best that we have come across is the one by Snurk (yes, that is the brand). It looks like one of those Olympic competition pools, so I guess it’s more suited for serious swimmers.
This thing is no fluff (pun intended), it is made in Portugal and designed in Amsterdam, and made from 100% organic cotton. It’s a duvet cover set by the way (with pillowcases) and is available in twin and queen sizes.
There’s also this style right here, which is not as impressive as the one above, but is quite okay.
This one is made from microfiber and also includes two pillowcases.
We’ll be adding more if we find some more cooler varieties.