Just in case if someone is wondering how it goes without cooling: I’m using the Pi 5 in combination with a SSD USB expansion (similar like this here) and Allos Piano 2.1 with Kali as reclocker. All in a more or less open setup (see picture)
I missed to order a heat sink so I’m running everything like this for the time being. During the scan of the SSD and simultaneous playback, the temperature rose to 63°C. When idling, it is around 6 °C less
So it doesn’t look like I’m going to have any problems with overheating. Nevertheless, sooner or later I will install a heat sink, because compared to the Pi 3 it is around 10 °C higher, which is certainly better for durability.
In terms of performance, the look and feel of the GUI is noticeably smoother compared to the Pi 3B. There are still some hangs, but I suspect that this is not due to the CPU but rather to bottlenecks in the network (e.g. when I access my NAS) or Volumio itself.
One thing I had forgotten is that I powered the Pi via Allo’s Kali, but now I need 2 power supplies (1x for the Pi and 1x for Kali) due to the higher power requirement. I tried it with just the power supply of the Kali which delivers 4.2 A, but like this the Pi did not boot.
But anyway, all in all a worthwhile change if you come from Pi 3, I think.
One thing I need to get familiar is the power button. If someone made already some experience it would be great to share it here. E.g. I’m not clear what happens to Volumio if I press it? Is it initating a shotdown in Volumio or is it just a hard shut off?