I got a base Denano a few months ago, I had a USB hub laying and and ran it for awhile.
The hub has 4 usb connectors on it so far I haven't had to power it either.
On it I run 2 SNES I-buffalos and a small wireless keyboard I also had around.
I've also gotten a blutooth/wifi dongle to work with it. Considering using my wireless 8-bitdo controller on it but haven't gotten around to it yet.
Actually a bunch of the cores run without any ram.
Then I got the ram upgrade.
I did an upgrade a few weeks ago and now there's tons of arcade cores on it. All the CPS 1&1.5 and a bunch of newer arcade cores as well.
Now is a good time to get one IMO because everything is now readily available for it. I strongly dislike buying some of these things online and you have to wait months to never to get some parts/stuff for them.
Just like I did you can start out small and keep upgrading as you like. HDMI plays damned near aspect and pixel perfect out of the box. If not there's tons of filters you can mess around with.
Loading times in almost all cases is damned near instantaneous.
Anyways, I'm all in.
Just order a standard I/O to try and get some RGB & analog audio goodness out of it.
I think in many ways it's easier to set up than a Raspberry PI. Once you get it up and running just go to update all scripts when plugged into the net. For a bunch of these arcade cores after you do that the games download automatically and show up in your list. Only thing is in general there can be poor documentation on updates. Say a core is updated with new features or a control scheme, you might have to go to the cores gethub page and sometimes it may still not be updated there in the readme file. You may have to find the info on the main mister page or some other news site or just figure it out on your own.
Also what new info can be poor.
Wish it supported chd files for Sega CD and Turbo Cd. That's what I'm going to myself. Had some crashes with turbo Cd files, long wait times.
I hope they make a IGM PGS core that'll be another 30 games or whatever and they can run like ass on a bunch on non PC emulators.
I'm sure CPS2 isn't far away.
I haven't tried it yet but I'm hoping for some good things for the Sharp X68000 soon.
Is it better than a PI? I dunno maybe. Some of these cores run amazingly, in some aspects better than the original systems. There's less systems though and less features, say like instant save or rewind. Most console cores have an amazing game genie like feature with an expansive database.
GUI doesn't look as fancy either.