I can dive back into MG just fine but I got into painting them too in late 2014 which like triples the amount of time it takes to make them. It’s strictly optional but even a bit of paint helps make them look much nicer.
FYI building Ikea furniture scratches that itch too, it’s like building giant gundams in the shape of mostly square furniture.
PS2s before that model have dodgy / picky lasers; the infamous DRE. You’ll find especially that CD / blue bottom games and DVD9 / gold bottom games might just not work. They also run hot.
Models after have some oddities… the 5000X and 5500X original size PS2s also have good lasers but the drive tray is not made as robustly. I personally had a 50001 disc tray snap some plastic off on the right hand side and not work property like 6 months after I bought it; I ended up making a DIY flip top case mod.
Some models starting around 5500X (and I think ending before the slim PS2) have this intentional design to cause the laser mechanism to overheat over time if it’s reading DVD-Rs. Yikes right!? There was a class action lawsuit about it.
The first model slim is OK, you can even do a complicated mod to restore the IDE interface, but it’s easier to just use an original PS2 if you want to load games from a hard disk / etc.
Every model after that has the MIPS cpu used for PS1 backwards compatibility and PS2 sound controller replaced with a PowerPC chip called “DECKARD” that runs an on-chip emulation of the MIPS cpu. If that sounds insane and buggy, well it is… works well considering but PS1 compatibility goes down, more concerning is that some PS2 games (even notable ones) get missing sound, sound hitches and skips, etc. It’s rare of course, you might not be fussed about it, but if you have other options might as well avoid.
The last models of slim units can’t run FreeMcBoot as the bug that uses was patched.
So really by process of elimination you’re best off with 3900X systems. The 5X00X series is OK as well if you stick to original media or are OK with the laser potentially failing with a lot of burned game use, allegedly especially lower grade DVD-Rs.
Nice thing about the 5X00X systems is that the PSU uses less power and generates less heat whereas the 3900X model I find if I leave it plugged in even when “off” (w/ red light on) it gets warm to the touch on the bottom, so I usually also turn that one off with the switch at the back.