I am not advocating this dot scope, and I wouldn't really believe it if you told me.
But, last week my buddy zeroed my $30 Walmart BSA at 50 yards. Then we did some CQB drills, time to go.
This week I shot it off a rest at 100 yards. I tweaked the sight a few turns of windage (remember he sighted it in  but I'm shooting it now).
I got a three shot group of 2". Out of a 16" Superlight Bushy. No comp.
I'm not an especially experienced rifle shooter.
I was definitely impressed with both the el-cheapo BSA red dot and the superlight Bushy flat-top.
Time will tell on the longevity of the optic.And the carbine.
PS I held low a little at the 100 yard range and the shots bullseyed the paper plate.

I read a few posts about how BSA optics were POS, but i bought the 42MM red dot anyway. My experience with them so far has been great. It took me a short ammount of time to get it sighted in at the range and my last 3 round group was touching at 50 yards. I plan on taking it out soon at 100 yards and beyond. Now, I am not LEO. I use my ar for fun and not duty so this scope was a great option for me. The only complaint i have is the scope covers suck.

inexpensive optics can do the same job only when they are relatively new. Usually, you will see the problems coming out as you shoot over 300 rounds or more depending on the recoil.

In the optics world, there is not much you can possibly save. You get what you pay for!

Duly noted. Notice that I said "I am not endorsing this red dot" and "Time will tell".
If there were only a local 3 gun match I could try it at.
I was more than a little suprised at how well it's working so far. I'm not counting on this carbine for any seriuos purposes at this time.