I don't play the number of CDRs that other people play, but I've played a couple of RPGs to completion on both Duo R and the original CDROM2 system like you have. I've never had a single issue and, as far as I know, we have yet to see any real science as to how they could harm a drive if they are burned well enough to play without excessive load times. If the drive is grinding away like mad trying to read code and the music keeps dropping out, obviously there is an issue. If it plays fine I don't see any reason to worry.
The original Duo however, that does have an issue where the sled gets stuck beyond the edge of travel and you have to manually wind it back. It "breaks" the Duo, but in a way you can fix yourself in seconds. It's possible the SuperCDROM2 does this too since they are or similar vintage and construction, but I don't know anything about that. I've never owned one.
In general though, this is old stuff. Run it until is breaks. Fix it, and then run it until it breaks again. Entropy is a basic component of the universe. Even if you put the thing in a closet and never fired it up it still might break just sitting there. The caps will still leak and the gears need regular exercise to stay free. Nothing lasts forever. Live your life and play your games.