Just got my Barch Designs Pi Holder machined aluminum case for my 4GB Pi 4. It's very pricey at $70 USD, but I figure well worth it for piece of mind on a machine running 24/7 and avoiding fan noise and dust.
Ran a sysbench stress test on it for 10 minutes and it did not go over 58C.
If you are interested in one, here is the link:
https://wickedaluminum.com/collections/ ... 5494435921
Makes the Pi into a tank, but I don't think it's for everyone. It is noted that it is likely to reduce Wifi and Bluetooth range, but I use neither of those, so I can't really confirm it in my use case.
I also ordered a Flirc case, but that has not shipped to me yet. I don't have too much hope that it can compete with this case, but it should do just fine for my 2GB Pi 4.
RPiB, RPi2B, RPi0, RPi3B, RPi3B+, RPi4B2Gb, RPi4B4Gb