What would be the most durable and future-proof CD-i player?

Considering the laser mechanism, CD-i member arsenixa tips the following: "I recommend getting an older 205/210/220 unit with a CDM9 laser mechanism. Those are much better than the CDM12. You can try to improve an old CDM12 by re-greasing the rails and cogs. That will usually fix "dirty disc" errors in games but playing a VideoCD from start to finish without stopping at least once is nigh on impossible. AudioCDs will usually skip a few times but those keep playing. CDM9 usually has none of these problems"
Considering the Timekeeper RAM: Most CD-i players are equipped with the M48T08 VRAM chip, when you are about to repair the Timekeeper RAM, you can either use MK48T08-150 chips or DS1643-100 NV chips. I've met CD-i member who claim the DS1643-100 NV chips are better.

"A good laser is not the only aspect. Some more things to consider:• Of course you should aim for a CDM 9 pickup, but also for a 32 KB NVRAM. Then, there is only one player left (220/40).

• If the CDM 9 breaks, then you will have to pay a lot (>100€) for a pickup assembly.
• If you don't care about NVRAM size then you could also go for portable players with CDM 9 (350 and 360). The capacitors start to leak, so all of them will need repair sooner or later.
• With CDM 12.1 and 12.4 you will get much newer and lighter players, but I would avoid CDM 12.4 because even the substitute VAM1204 is rather rare/expensive.
• CDM 12.1 substitute = VAM1201 and VAM1202, easy to obtain and not too expensive at the moment.
• I don't want to go too deep into clock chip topic. Bottom line is, they will all eventually die in some years, not matter which size, brand or age. Everything else is simply a question of money if you want to replace them with new parts. (I'm not a big fan of hacks.)
• And I haven't touched other aspects and personal preferences (e.g. non Philips players, remote control and DVC compatibility, input ports, RGB output, etc.)."

Muh Mullet: "The CD-i 450 does have a manual disc loading bay, so no issues with tray-belts stretching and causing the tray to get stuck half way. And when modded for RGB, they are as versatile as their older brothers, and less bulky too."

Adrian Zanoli: "The 450 lens is still in production and cheaply available for the same price of a timekeeper. Maybe the main problem is the need of modify the power input with something more standardized than the original ethernet cable."