FTN.4 Failure

I have a few questions on the FTN as we get closer to Jan 1. I plan on submitting quite a few form 1s. This is my original form 1 that had a failure after less than 200 rounds. The particular day of failure was very cold and failed after only 2 standard capacity mags back to back not rapid fire. I followed PLAbois guide to a T.

1. Is the FTN.4 the most solid 3d printed suppressor so far? Best performing?
2. Best mounting method? I used KAK micro flash hider.
3. Any other suppressors worth looking into? 5.56 as well as other calibers?

This failure happened with an 11.5” KAK “suppressor only” barrel. The core is annealed polymaker PA6 and I used a liberal amount of JB Weld.