The bike is a great value. Made of 6061 Aluminum, it is both stronger and lighter than bikes made 10 or 15 years ago. The shifting group on the bike is entry level but more than sufficient for this level of bike. The brakes are wonderful, and the tires, although heavy, are quite acceptable. The front shock is pretty much crap but shouldn't cause you trouble (i.e. it is unlikely to break), only extra effort. Overall, though, it is hard to find as much bike as this at this price level. The big brand names cannot touch this bike at this price.
So, should you buy it?
To answer this question, you have to ask yourself, "What do I want out of riding?" There are many valid answers to this question, so think about it. Are you planning on riding the local gravel trail in town? Are you planning on short trips around with the kids? Would you prefer to ride actually two-track trails with roots, stumps, rocks and sand? Or are you looking to do distance riding with friends?
Answering these questions honestly will go a long way toward deciding whether this bike is for you. So what is this bike best used for? This bike is almost exclusively for riding gravel trails around town with the occasional off-road or two track. It is NOT meant for riding around town and definitely not for distance riding. Similarly, it shouldn't be bought if you plan on riding technical trails with drops and steep climbs.
Let me back up my unfounded statements. Gravel trails are easy to ride and you could easily get away with a touring bike (defined as thinner tires and a more upright, laid back riding style). But every so often, you will hit a patch that could puncture your tire and/or tube on a touring bike. The Kenda tires and soft shock will keep that from happening on the Response. Similarly, the low gear ratios on this bike will make riding up hills much easier, as long as the path is not too rough. If you are doing steep inclines on a bumpy road, the crap shock that comes with this bike will feel like a pogo-stick, causing the front tire to lose grip with the road/trail. This will most likely end with you walking the bike up. But in well maintained trails, you should excel.
If you are riding around town, you'll see lots of surburbanites riding their Treks and Specialized mountain bikes. You would fit right in with this bike. However, you would be better served by a touring (sometimes called "hybrid") bike. Something like this:
Diamondback Edgewood Men's Comfort Hybrid Bike (700c Wheels)I know, it is not as cool looking. And looks should factor in since you want to feel good when riding around town. But that less cool looking will translate into higher speeds, less effort, and more comfort. If, on the other hand, you are planning on riding technical trails, you will need more gear. You could buy a better front fork (at a minimum, something like this:
RockShox Tora Coil 302 U-Turn Fork (Black Pl Rim/Disc, 85-130) ) but really, you'd be better off spending more on a lighter, more complete bike. You should expect to spend at least 50% more on an entry level bike for more serious downhill and technical trails. If you are over 5'10", you might even consider a 29-inch mountain bike.
Finally, if you want to do distance riding, the bike is wholly inappropriate. The riding stance and the tire thickness would make this bike (or any mountain bike) a poor choice for anyone other than the most fit athlete out there.
In summary, this is a GREAT value bike, oodles better than anything you find at your local discount market. Moreover, Giant, Specialized, and Trek cannot touch this price point and, although you must compromise on weight, front fork, and grouping, you will get a whole lot of bike for a low price.
By the way, yes, I both own and ride this bike, along with my Giant TCX Crossbike.
UPDATE: The day I wrote my review, the bike was on sale. Now that the price is back up, I would knock off a 1/2 a star, since the value is diminished. I'm not saying it's not worth Amazon's price, only that if I were you, I would consider waiting for a sale.