It's funny you say that because a90 deleted all their 5 star reviews on the product (maybe kept a few to seem not so-sus) and I posted a review that got deleted due to "discontinued" unless it was a bad review.I would take the "Armytrix quality is bad" claims with a grain of salt. I saw that A90 shop posted about the bad quality on their website (which is very sus for a reseller to do that).
All the reviews on the forums from what I read are pretty much always good. If you want a catless downpipe that doesn't throw a CEL then Armytrix is by far the most reputable one, with Kenji being seconds.
I just ordered myself an Armytrix and will post back in maybe a week with my initial thoughts.