What do you mean “hobby grade”?
You do know many police officers use M&P AR15s and they’re one of the best values out there.
You do know there are YouTube torture tests of PSA AR15s that show more abuse than those “operators” who were in the “sandbox”. Sorry but some “vet” “expert” whose job it is to get you to spend more isn’t who I’m going to listen to when he doesn’t even know what AR stands for.
Worse you could do a simple search using Google or Bing or your favorite search engine and see that “expert” is wrong.
Based on your replies I’m wanting to say you’re trolling. But I’m going to stop short of that as I don’t know if you’re sincere or not.
So I’d suggest you take some time and do some homework. And if you don’t like what you find listen to your “experts. Personally, I have a friend here who is in law enforcement and is a retired Gunny. Many here know him and trust him and I’m willing to bet if he says it’s right then it’s right.
As for parts quality, some things are easier to figure out. Barrel material and construction add to cost and reliability. But add trade offs. Triggers typically are something you pay more for to get a better product. But even there you can find value.
Stocks are all over the place but cheap ones rattle and are annoying while ones that cost hundreds can look cool and tactical and give no extra value. In between are tons with all sorts of pros and cons.
I’ve yet to figure out grips. Basic grips work and are cheap. But free float ones are all over the place in quality and price.
LPKs can be junk or value like PSAs. Again price isn’t always an indicator of what you’re getting.
Now get a Daniel Defense rifle and you can probably say it’s full of good parts. They and other top tier companies cost a lot and use good parts. But it doesn’t mean they’re “operator” or whatever hip and cool term you’re using quality.
So yes I’d rely on my PSA, a M&P or similar rifle to defend my life. I also wouldn’t trust my more expensive 3 gun rifle. The later being more of a “race gun” than a reliable workhorse.
Again I’m not slamming you but showing that there is a lot out there and not everything as it appears (including your LGS “experts”). And I don’t claim to be an expert, but I know enough to assemble a reliable AR and enough to put together a nice competition gun on a budget and have it do it’s job. To me those are things that matter, going bang and hitting the targets.
For starters, PSA and M&P are definitely hobby grade.