If I could give it ten stars I would. My buddy and I got matching Dos X's for a disc trip and right out of the box they performed perfectly. That was more than a year ago, and I still throw this disc every round. There is a running joke in my dic golf clan that if there is a tought line where you need pinpoint accuracy, you "grab the Dos X!" Mine hasn't aced... yet. 

The 4 glide is real, and this disc is predictable no matter the wind. 

Thrown flat, it flies straight about 1/2 of flight then pushes into a long fade that dumps at the end. Thrown on hyzer, you pick the blade of grass you want to hit and this disc will bomb right on top, the more airspace you use the less it will want to skip. It is a very unique disc and is a definite staple in my bag. 

The Dos X is a very dependable, controllable overstable fairway driver, and my go-to for shots that fit the Thunderbird/Teebird3 slot in the bag. Not very forehand friendly, due to the dome, but one of the most comfortable discs in the hand that I have ever felt. 

On a forehand release, the turn is evident out of the hand with reliable fade. The problem I have with the Dos X though is a lack of glide. I have tried several different releases and each time this disc simply wants to get to the ground 

The Dos X was a lot more stable than I anticipated. I like it as a very controlled driver. Check out this unboxing and initial impressions video:
 

Signed up to this site just to review it, since there's only one other review and I'm quite a fan. Flies just like the numbers in my opinion, and really fits nicely between a 7 and 9 speed. It's like a slightly faster discraft stalker, or slower innova thunderbird. It's surprisingly torque resistant - I can throw a distance driver 450+ and when I really rip this, it doesn't turn over too much on me. For me I like it on straighter lines without too much side to side movement, and a reliable left finish right around the 350ft range. Slower arms (300ft max and less) will probably find it to be relatively overstable, and won't quite see the numbers, but for me it's very accurate. Bigger arms might be able to turn it over more, but I'm not sure to what extent.

Other 8 speeds I can compare it to would be a MVP Volt in fission which is more stable than the Dos X, and the Westside Bear in Ice VIP, which is also more stable for me. I get more glide out of the Dos X than the Volt, and similar glide compared to the Bear, with no issues with it wanting to turn over and go off line. I don't have a Teebird3 which would be probably be a good comparison.

I recommend it for people throwing 350+ that want something stable and reliable but not a hook and not too fast. If you're under that distance, expect zero turn and stronger fade.