Dell Optiplex 7010, i5-3570, 8GB ram, Nvidia GTX 750, dual monitors, Samsung 250GB SSD + several TB w/spinning drives
Devuan Ascii XFCE

So I finally took the plunge and upgraded from ascii to beowulf.  First off - I still remember doing upgrades back on RedHat 5.1, so I've been doing this a while.  Linux upgrades sure have come a long way!

My first issue was that I had held back all nvidia packages, so I had to take those off hold before I could get dist-upgrade to start.  Not a problem really, but a hurdle.

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FIXED ISSUES (worth mentioning):
dist-upgrade went fine, no real surprises until the end.  There was some issue with the nvidia driver.  A reboot might fix it.  It did not.
No X server.  Tried quite a few things to get it going, I had part of driver 390 installed and part of 418.  I ended up uninstalling all the nvidia drivers, and then trying nouveau.  No go.  So reinstalled only the latest nvidia.  Using "X -configure" gave me what looked like a good xorg.conf file, but then X wouldn't start claiming the number of screens didn't match my hardware.  I copied over the xorg.conf file that I had backed up before the upgrade, and all was good with X.

Next issue was slim.  It was gone.  I had done the auto-cleanup per the instructions, so maybe that got rid of it?!  Installed it, then I was back up and running in XFCE. 

Pulseaudio wasn't running.  Long story short... I fixed it by launching pulseaudio via autostart and disabling start-pulseaudio-x11 which didn't seem to be working.  Then I found the right answer in the release notes. D'oh! 

sendmail was taking 60 seconds to start on boot.  I know I had seen this in the distant past and fixed it.  Just needed to update my hosts file appropriately to have the non-fully-qualified hostname as the first line.  Which I already had in ascii and it didn't change, just needed to change the format a little.
(ascii) 127.0.0.1    localhost ip4-localhost ip4-loopback
(beowulf) 127.0.0.1    devuan devuan.localdomain

I run serviio as a dlna server.  It wasn't working anymore.  Messed around with it a bit, then just installed the latest version and default-jre (missing) and it's back.

Was getting an error in syslog from console-kit-daemon about cgmanager not running.  It wasn't installed, so I installed it.

VLC was gone, as was Handbrake.  Re-installed them.

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UNSOLVED ISSUE:
I see a 30 second delay before the desktop comes up.  Here is the relevant portion from syslog:
...
Jul  4 10:24:24 devuan avahi-daemon[2001]: Server startup complete. Host name is devuan.local. Local service cookie is 2967303762.
Jul  4 10:24:26 devuan kernel: [   13.476220] resource sanity check: requesting [mem 0x000e0000-0x000fffff], which spans more than PCI Bus 0000:00 [mem 0x000e0000-0x000e3fff window]
Jul  4 10:24:26 devuan kernel: [   13.476373] caller _nv029707rm+0x58/0x90 [nvidia] mapping multiple BARs
Jul  4 10:24:26 devuan kernel: [   13.770321] resource sanity check: requesting [mem 0x000c0000-0x000fffff], which spans more than PCI Bus 0000:00 [mem 0x000d4000-0x000d7fff window]
Jul  4 10:24:26 devuan kernel: [   13.770476] caller _nv000935rm+0x1bf/0x1f0 [nvidia] mapping multiple BARs

**** Note the 33 second delay here.  Did some googling, but no real answer yet.

Jul  4 10:24:59 devuan dbus-daemon[1976]: [system] Activating service name='org.freedesktop.ConsoleKit' requested by ':1.7' (uid=0 pid=2268 comm="/usr/bin/slim -d ") (using servicehelper)
Jul  4 10:24:59 devuan dbus-daemon[1976]: [system] Activating service name='org.freedesktop.PolicyKit1' requested by ':1.8' (uid=0 pid=2606 comm="/usr/sbin/console-kit-daemon --no-daemon ") (using servicehelper)
...

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Kind of annoying, but I honestly restart my machine every couple of months, so not a huge deal.
Other than these few hurdles, everything seems to be running great.  Somehow, memory usage is even lower than it was on ascii.   I didn't take a "before" snapshot, but I know it's lower by quite a bit.
 
Right now as I type this I am only using 1.5 GiB of RAM !  Here are the top 10 users from ps_mem.py

12.6 MiB +   3.1 MiB =  15.7 MiB    xfce4-panel
17.6 MiB + 943.5 KiB =  18.5 MiB    libvirtd
17.5 MiB +   3.3 MiB =  20.8 MiB    xfce4-terminal   (3 terminals with 4 tabs in each)
14.2 MiB +   9.1 MiB =  23.3 MiB    flameshot
20.9 MiB +   2.4 MiB =  23.3 MiB    redshift-gtk
14.5 MiB +   9.6 MiB =  24.1 MiB    qasmixer
43.9 MiB +  19.2 MiB =  63.1 MiB    Xorg
53.4 MiB +  17.2 MiB =  70.6 MiB    xfdesktop
386.1 MiB + 334.5 KiB = 386.4 MiB    java
690.9 MiB +   5.4 MiB = 696.3 MiB    palemoon   (7 tabs open)
---------------------------------
                          1.5 GiB   

I may run into a few more things here and there that aren't quite right, but I shouldn't have any issues resolving them.
Overall, Beowulf gets an A from me!