PROS: A lot of features for a very low price. Shocks on the front, spring loaded isolation from real wheel, on-handlebar twist-type gear shift, 21 speeds, nicely constructed.
CONS: You get what you pay for. Wheels, components, and handle grips are mediocre quality. I had to spend about two hours adjusting the brakes and derailleurs before it was ready to ride. But that puts it in the category with my $500 road bike when it arrived. I was a little annoyed that the adjustments were so far off, and being an inexpensive bike it takes three hands to squeeze the derailleur the right way and tighten the cable bolt. After a little trial and error, I finally got it. And those little crimped caps on the ends of the cable kept coming off because they had been improperly crimped at the factory. There seems to be no place for a bottle cage or frame pump. My bike had poor threads on one crank so it was impossible to install the pedal without cross threading. Also, the plastic guard on the large chain ring broke after transporting the bike on several trips. In my case, I simply removed the broken guard and forgot about it. The derailleurs need periodic adjustment and there are no fine adjusters.
This bike arrived about 4 days after ordering it on Amazon. It came reasonably well packed, though I can imagine a lot of damage from a careless delivery truck. It's just perfect for riding the trails that are in the mountains where we go camping. I did not want and did not expect a $1200 mountain bike, and I got what I expected.
When properly adjusted, the ride is better than I expected for under $160. My wife has the women's version of this same bike, and it takes a little more getting used to for her, because she is not accustomed to keeping only her toes on the pedal or the responsiveness of the steering. The flip side of more control is that you can flip over easily if you are not careful. Also, if you pull the front brake harder than the back brake, like any mountain bike, you are going over the handlebars on your way to the emergency room. But you can't blame the bike for being what it is advertised to be.
The frame is constructed of heavy duty welded aluminum alloy, and it seems rigged enough for the casual user. I don't plan to jump 5 feet in the air with hard landings, so the bike is tough enough for me.
WARNING: Mountain bikes are high performance bikes like road bikes. I recommend against getting one for a child. If you don't want to be bothered with toe clips, you probably shouldn't get mountain bike. If you think you should be able to use all 21 speeds - STOP. If you think you feet should be able to rest flat on the ground when you are on the seat - STOP. If you don't know and don't want to learn to adjust the cables and derailleurs with tools - STOP. Like all bikes with lots of complex parts, these bikes need frequent maintenance. Be prepared to spend the time doing it, learning to ride it correctly, or take it to a bike shop for professional maintenance. Otherwise you or your child could be injured. If you just jump on and try to ride it like and old cruiser bike, you run the risk of putting your foot in the spokes of the front wheel and flipping over.