Setup works reasonably well via Matter, for anyone wondering. They actually show up as two separate devices, one for their native app and one that's compatible with Feit Electric, and both showed up during Matter setup. I'm using mine with an Echo Show as a Matter hub and they don't have any connectivity issues once connected.
They're reasonably bright with good granularity in the brightness controls. The Red and Blue colors are spot on, but the Yellows end up being a lot more Green than they should be, so you have to play with them to get the correct color. Setting them to "Yellow" ends up lime green, while "Orange" ends up very yellow, but "Scarlet" yields a reasonable Orange so it's really more a matter of terminology when setting them.
One of my four bulbs wouldn't connect directly via Matter no matter what I did. I ended up connecting it to the Feit Electric app, which these are thankfully compatible with, and then sharing it via Matter from that. This yielded a different Matter code than what was printed on the bulb, so I believe it was probably just a misprinted code. It works perfectly fine via now that this is sorted, though Alexa could NOT find or control it via the Feit Electric skill.
Build quality seems fine, about what you'd expect given the price point. They don't seem particularly fragile or anything.
Overall I feel like they're solid value for the money. They aren't on par with a Hue or LifX bulb, but those are 2-3x the price I paid. For $21, I would absolutely buy these again.
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