ATI Alpha Maxx 5.56 NATO 7.5" Barrel 60rd Optic Ready AR-15 Pistol Matte Black - $298.03

This is from the other member who bought this exact deal.
Here's what he said if you didn't already read his comment
"Trigger and hammer is polymer as well so I made swap lowers".
This is exactly what I was talking about when I said the confusion and mixed descriptions are hard to know what's what.
In no way would I want an all polymer gun that also has plastic triggers and hammer. Like seriously, a plastic hammer on a rifle is like trying to use a child's plastic toy hammer to build a house....no thanks, nor am I buying something that you have no idea of exactly what you're getting. Is it all polymer? Is it aluminum lowers? Does it have steel or plastic internals, etc etc.
I don't care how cheap something this firearm is, beyond an occasional range trip, these are not my choice for defending my family. Over time polymer WILL ABSOLUTELY crack and or warp over time due to heat and high pressures. If it was just a lower that was polymer then I could accept that but the upper, chamber and internals being polymer? Nope.
Why do you think that every single generation they come out with has had more and more METAL reinforcement molded into the stress points of the firearm? If polymer doesn't warp and or crack over time why add the reinforcement? It's because they know.

Glad to hear you are happy with your pistol. It's hard to keep track of specific "SKU's" and that many of these advertise a plastic trigger and internals. Same with the polymer upper and lowers but some are aluminum uppers, etc. The description says this one has an aluminum receiver? I can tell from the pic that at least the upper is polymer. You can tell by looking at the shell deflector. For an occasional range shooter these are probably ok however someone like me who shoots at least once a week, hundreds of rounds a month, I don't believe these would hold up as much as an all aluminum and steel weapon. Polymer DOES warp and breakdown over time from heat and pressure. Over and over the rapid heating and cooling causes breakdown. I don't care what anyone thinks, this is fact. Why else would these companies offering all polymer guns, every new version keeps getting more and more steel "reinforcement"? So yeah I'm happy for you and that your happy with your gun, overall that's what matters most.

So what's your verdict? Is the plastic parts actually functional?.how many rounds you put thru it so far? Does the polymer trigger and hammer holding up?

Agreed! Not just polymer lower and upper but even the trigger pack and internals are plastic. If you want something to just sit in your safe and not ever be used, I guess it will work but anyone with commen sense understands that plastic and high pressure, high heat do not mix. At some point shooting your gun. Heating it up, cooling it down over and over, shooting sustained fire, and in all types of outdoor environments is going to crack and or warp the plastic parts. They can say that certain parts are reinforced with metal but that right there should be a red flag. Over the years they've had to add more and more "reinforcement" due to failures in the polymer. So all they've done is add bandaids to the biggest problem... Plastic parts! Spend a few more dollars and get a PSA, BCA, Anderson, Kerris guns, all aluminum firearms. Don't get tempted here with the price.... Save the Tupperware for the dishes, not your AR firearms.