First off, I don't know what happened to those who had bad experiences with their Havoks they purchased. Mine has been flawless when used properly.
I'll give a bit of backstory on how it has been used:
I'm a adult who got back into the "Nerf" hobby when my 2 girls and I dug up a bin of my old dart guns from when I was a kid and all of a sudden we were having tons of fun with them. Needless to say I start going to look for newer & better models and shortly I find that I have a entire arsenal of blasters from all brands that has now reached 100's in total, requiring my garage to be refitted with dart gun mounts all over the walls and we have about 4,000-5,000 darts for full-scale neighborhood wars (yes, the neighbors get in on the fun, and it normally crosses anywhere from 2 to 4 yards in total).
With that out of the way, you get the idea. We have lots of experience in using dart guns, and they get passed around (I keep 3 bins of loaner blasters that I put out for anyone and everyone to feel free to use) and used heavily and hard. The Dart Zone Havok is one of the "loaner guns" and sees use by people from 7 years old to me at 31, to those in their 50's.
What is good about the Havok?
-Fantastic ranges and power. It will hit 50-60' with zero issues and can reach the claimed range if you angle it up and let the dart sail.
-Rate of fire. It can follow up shots pretty quickly and consistently. That side priming lever is easy to pump despite the stronger spring.
-Ease of use: The clips (yes, these are clips, not magazines) have arrows molded in them that show directions of which way is up and which way is forward. A quick glance is all that's needed for even a first time user to get the idea.
-Comfort: The grip and side lever have a nice feel, and aren't sharp or cramped for myself, not too big for a kid. Nice balance.
-Value: You get a nice performing blaster, two clips, and darts for $10. That's awesome.
-The clips are only going to work with this gun. You'll need to grab a couple more from Dart Zone's website if you want to use this blaster as a main Nerf war ready primary weapon. It has the performance, you just need to buy more clips.
Other than that, you have a dart gun that works well, feels well, and will outperform every Nerf brand pistol and do all of that at a great value. A big thumbs up from me!