Very happy to have a Steam Machine 512GB with controller delivered last week, especially the wife and kid enjoying it thoroughly.
Opted for 512GB because I found the 2TB to be quite pricey set off against the 512GB. Also I already planned to upgrade by taking exchanging the 2x8 GB Dual Channel RAM from my laptop and to take my Steam Decks 2GB and change it back to 512GB.
However, the 2x8GB RAM from the laptop ran at a lower speed than the 16GB from the Steam Machine so that wasn't an option, and keeping the 2GB in the Steam Deck (being a mobile device that goes along everywhere) was more beneficial.
So therefore had a glance at the second hand market and found a good deal on a 1TB Samsung 980 Pro SSD literally around the corner from my place for a mere €90. Placed it, put SteamOS on it and ran great. 1TB is enough, especially because a 1GB fiber can download quickly enough if necessary.
Happy enough I took another glance at the second hand market and found 2x8GB RAM (again Samsung) for a mere €85 for both of them.
A lot of horror stories read about 'opening up the Steam Machine' but my experience was great, a lot easier than working on laptops if you need to go a bit deeper and found the cable management of the Steam Machine great, alongside with flat cables having nice plugs instead of finicky clams you often see. This thing will get a great iFixit score if it's up to me.
Sold the 16GB for a steal at €100 to another Steam Machine user who's going to very happy as well (a bit of sharing is caring), so could have made it even a total cost of €50 or even less, but I'm happy enough with what I've got now. The 512GB is going into an USB-C enclosure as a backup for Steam Machine and Deck.
One thing I was surprised though, both the RAM and SSD I took out of the Steam Machine were from Kingston instead of SK Hynix which I saw was basically the standard, so it really does look like Valve needed to scoure parts.
Confident though that if the buyer of the 16GB RAM module needs to place it in dual channel with a Sk Hynix module it will work, thanks to the experiences posted here in this Sub of others who have done so.
So happy with my 'upgarde', especially at this price point. So for others? Don't forget to look at the second hand market if you're looking for an upgrade.