I finally got around to adding one of these to the bag to complement my Ibex and I wish I would have sooner. I can smash on this thing as hard as I want and it never ever turns. I have even tried throwing it pure anhyzer to see if I can get some left to right movement out of it (RHBH) and NOPE! It just fights right out of it. The best part is it does not have a huge dumpy fade. When powered up (around 400ft. max power) It basically just flies out dead straight for about 250 or so feet before starting its reliable but mellow fade landing at about 300ft maybe 25 ft. left of the line it was released on. It pretty much ends up being a slower Teebird for me that sticks where it lands. If you are a beginner I would avoid using this as your mid. You will probably end up with better control and distance just throwing your putter. That being said, if you have moderate power and are looking for a disc that you can throw near full power with confidence it will fade left at the end and then stick where it lands, this may be the disc you are looking for. 

The flight numbers I have linked seem to be a more accurate pattern than vibram has listed. I personally would ignore the factory flight patterns on this one and go what people are saying so you know what you are getting. I am not saying this is a bad disc however. I have a 171g and I mostly forehand throw. The factory flight states that it would fly like a brand new max weight roc but out of the box it flies more like my 165g very beat in dx roc. I have gotten a straight flight pretty easy but I have to release with hyzer to do that. Its still in my bag tho as a straight flyer

To be fair this review is based off my experience with a disc I got used.  The prior owner claimed it had only been used for a couple rounds so I am presuming it is not a totally beat in disc.  It is a 170 g x-link medium.

I bought it to be an overstable mid.  It is not as advertised.  The one I have actually flies quite understable.  It is less stable than my 170 g esp buzzz.  I didn't like the flight path or feel as well as my 170 g lucid tursas so this disc has left my bag.

This disc holds the line I put it on. I would not say it is very overstable, but that doesn't make it a bad disc. It is my go-to midrange disc and I love throwing it on an anny and watching it glide slowly back to straight. I recommend it highly in a medium weight. My first one was max weight but I prefer it lighter. 

I think Omniumx nailed it - very strange disc, and the subject of much conversation at the last 2 Birdie Bashes I've played. It is not comparable to other overstable mids: it turns over far too often, at least the 4 or 5 I seen thrown and thrown myself. It behaves as a OS mid if thrown very softly, or on a steep hyzer. I wonder why Vibram picked Ascent and Trak as discs to re-do, as Obex doesn't really fit the bill, whereas those are good discs IMO.

I've been trying to find a disc that works for me as a straight, reliable midrange. I've tried about ten Innova discs and then this one. I bought this disc (173g X-Link Medium) for my girlfriend as her first disc and when I got to throw it I was shocked at how much I love it. The grip is perfect and it just flew right for me. I don't agree that it is overstable, necesarily, but it is a fantastic disc!

Played in a Birdie bash today and used this disc for every throw of 36 holes except 5 shots. 

Positives: It flew very smooth. Once you figure the disc out, it can be very versitle for upshots. 

Negatives: Does not qualify as an overstable disc. Cannot handle torque well. If I didn't know better I might even mistake this disc for a stable/understable disc. The "grippy" rubber was actually rather slick in my opinion as well.

I still wasn't entirely disapponted with the disc even with the inconsistencies, just because of the smooth flight. It also grabbed the ground well.

So far this disc has been great. This disc flies incredibly straight. I also love the feel of this disc. My go to mid in open fields

I just played in a Vibram birdie bash, and got the Obex in the Medium X-link at 173g. The 1st round was about 50F and the grass was wet. The Obex was brilliant and i was thinking it would nock my Wasp out of my bag.The medium X link feals great in the hand and is just about invincible. However, when we came back for the 2 round it had wormed up to 70f ,and the grass was dry. With no wet grass to cool this disc down and the temp worming up the obex changed drastically in flight and feel. All disc will do that, but i have never had a disc do it as much as the Obex did. It took me a few throws to adjust. All in all this is a great overstable midrange with great glide.