This is part of a comment I made in a reply to a bug report:
[words in red were added to add clarity to the copy/pasta from the reply]

I'm currently running a full battery and enough flawless to run one [flawless crystal] in each slot for the first bonus in Agony, Chaperone, Merciless, Monster and Rampage, with the 6th usually Volcanic or Voltaic depending on which loadout/weapons I'm using.

My Replication set has 2 cut and a polished, so, NFW, it's not even on my radar.

My luck with the flavor of the month event syns is pretty dismal.
  • I have a single polished in Predator.
  • I have 5 cut and a polished in Aegis.
So I totally discount the new syns until something awsome drops, and it aint happened yet besides the 3 flawless I pulled in Monster.

Out of the last 20 to 24 flawless caches I saw/bought since before the start of the Volge Winterfest- I got 2 [regular syn crystals] that didn't turn to dust.
And since nothing of note drops at arks naturally but garbage, I don't expect to pay any attention to this syn either.

[End of comment.]

Is anyone else doing much better with the event syns the last few events that they make good use of it/them?

I don't recall seeing any 'Event crystal flawless caches' available for purchase at the end-of-ark vendors.