tl;dr: 52Pi and Seeed Studio's water cooling solution for the Raspberry Pi 5 can be fun, and works better than any other solution—but at a steep price, and with a number of annoying quirks.
A few months ago, 52Pi reached out and asked if they could send a new water cooling kit they were working on for the Raspberry Pi 5. At the time, the hope was we could figure out a way to get very high overclock with adequate cooling.
Unfortunately—for reasons I'll explore more soon—the Pi 5 can't overclock beyond 3.0 GHz (it's not physically possible). Some of why is explained in my blog post Overclocking and Underclocking the Raspberry Pi 5.
But water cooling is still fun, and the product is in production now, so I figured I'd still give it a fair shot, and see if I thought it might be worth buying for certain niche use cases.