The switch is plug-and-play, everything just came to life and started switching after a minute or so. I've since moved the power lead to come from directly behind this is what the feature allows you to do without turning off the switch. It came in a plain brown box with a glossy product sheet glued to it: I snagged the last one available in Canada off Amazon. The price was pretty good especially in comparison to the other switches and it was actually available. Since I didn't need 10 G right away and I could just use SFP+s when I do, I got the -2S version. The M2108s come in 2 versions: the -2C with 10 G combo ports (RJ45 copper or SFP+) and the -2S (10 G SFP+ only). 8x2.5 GbE ports, managed, 2x10 G SFP+ ports, supposedly fanless.
In the list on that thread I missed one switch which was released in December 2020: the QNAP M2108-2S. I'd need one or two 1 Gb RJ45 SFPs in order to have extra ports available, just adding to the already high cost. Ideally I would go with the TP-Link TL-SG3210XHP-M2 because I'm starting to use and like PoE+ and the TP-Link Omada controller application is quite good, but that switch is quite expensive, has 2 loud fans and won't have enough ports if I move over all my 1 GbE and 2.5 GbE connections to it. The chip shortage and supply chain issues have increased prices and decreased availability. We covered most of them here and there hasn't been many/any new models since. There hasn't been much development in the 2.5 GbE managed switch category though. Other unmanaged 2.5 GbE switches have since been released from TRENDnet, TP-Link (5-port and 8-port versions), Ubiquiti, and QNAP has also released the 8-port version of this switch, the QSW-1108-8T. It was and still is the lowest-cost 2.5 GbE switch. It's unmanaged with few features so there's not much to talk about.
It's been good, it's worked reliably, cool and quiet, keeping connections up and switching at 2.5 GbE wire speed (about 2.37 Gbit/s). For almost a year now I have been using a QNAP QSW-1105-5T to serve my 2.5 GbE switching needs.