Overall, the rack is very good. Butterfly locks are solid, side clasps look sturdy, rails for 19" unit fixation are good.
Only thing one can budge about is that the lids might not exactly fit the rack down to the millimeter. Once the butterfly locks are closed, nothing is ever moving, but you can see the aluminium sides are sometimes a bit offset with each other. I believe in some cases, lids are not swappable because of this.
Other than this, nothing to complain about.