my experience with modular is good, if i compare with other synth manufacturers i will say it can stay in the top tier devices .
usually knobs are bolted to the faceplace and i have only one or two that seems to be getting old( i have 2 cases for 6 years now).
i tend to stay away the most i can from the tall trimmers modules as they're plastic shaft and tend to be wobbly.
my 2015 braids i bought used is still working fine ( the encoder is very smooth and has a tendency to skip menu items but it works ). as every hardware you'll need maintenance sometime but i feel i can go a long with my eurorack. i hope ..
look at vintage synth ,some are still going after 30 years.