A few things, most of which will sound silly, but I too am silly.
The etched emblem/logo is off center.
Found it hard to find the push button with thick gloves if I turned light off, which I often do on night dives.
The one proprietary (?) O ring bothers me.
The threads squealed high enough to shatter glass out of box.
I bother easily, get put off things easily.
I like German lights, MB-Sub (no longer trading), Tillytec and Metalsub out of the Netherlands.
Don't get me wrong the CX2 is a fine light for the price, I just don't love it as much as I need too in order to keep it.
$135 shipped.
YMMV