When it comes to ANY weapon, you need to do your research. The BEST place, is to go to manufacturer SPECIFIC forums. I.e. Go to the S&W forum to learn about the M&P's. There are forums or sections dedicated to most manufacturers. This is where you'll get your best information.
When you're on a manufacturer specific forum, all; if not the overwhelming majority; of posters own that brand. Therefor, they are much more honest with each other. There is no competition and there are no egos. If you're on the forum that is for olympic or bushmaster or M&P, etc... you normally don't have the Colt, LMT, or BCM crowd giving biased and prejudiced opinions. Every manufacturer; including the MOST EXPENSIVE AND WELL KNOWN; will have at least one customer that was totally dissatisfied and thinks that brand sucks and is the worst.
Go to the manufacturer specific forums; not forums like this one or other generic firearms forums. See how many posts start with: "Need Help"; "Why can't I....."; "Is this normal", etc.... Basically, look for negative/problem posts. Then, compare that to the number of: "Look at my new toy"; "I'm so excited"; "What accessories"; and other non-problem threads and posts are started. Now remember; forums are generally made up of 2 types of people. Those looking for answers to their problems; and "enthusiasts/hobbiests". What that means is, most people who are "Happy" with their item, aren't going to come to a forum to tell be they are happy. It's usually those who have a problem. So; if 1 in 10 threads are about problems, that DOESN'T MEAN THAT 10% OF OWNERS HAVE PROBLEMS!!! Less than 5% of people participate in forums. That's for ANY subject. cars, PC's, home theater, guns, skiing, etc... We're a very small minority. But if you can go to the S&W forum, and discover "X%" of threads started are negative or need help in nature, then you compare that to the Olympic, bushmaster, RockRiver, Colt, Daniel, LMT, etc... forums; you'll be able to determine who seems to have more issues.
This is the ONLY way of determining the "Overall" quality of a specific rifle or pistol. A person telling you a Colt sucks, means absolutely nothing. Neither does them telling you it's great. Individual accounts and experiences are too biased. ESPECIALLY on a generic forum like this. When a person pays $500 for a scope, they WILL rationalize it against ANY criticism. You will hear the "You get what you pay for" and every other excuse. Rifle/pistols are no different. There are some manufacturers that live off of their name, even though their product has proven to go down in quality. Sorry; but Bushmaster is a prime example. They are NOT the bushmaster of 20 years ago. Yet, their normal price for an AR is above $1000 in any gun store. "Except for the new carbons". That price is strictly because of the name they are selling. And people who buy them, will justify and rationalize those prices. Forget price initially. Look through the specific forums and see what the users of those products say. Especially if they aren't being bombarded by people of OTHER BRANDS. If everyone on a forum is an S&W, Rock, bush, Colt, etc... owner; then you don't feel as bad complaining publicly. Everyone is in the same boat. When you're in a generic forum like this, you'll get the stupid replies like: "You shouldn't have bought that"; "You get what you pay for"; etc...