No, it was pretty crappy.
Gregor's actor had no notion of how to swing a ****ing sword (Compare to Conan Stevens' Gregor fighting Sandor). Oberyn's choreography (Possibly because they actually had a stunt double for him, idk) fared better, even if there was a bit more flipping than I'd have personally liked. Oh, and why the **** was Gregor by and large swinging his sword with one hand? Eschewing a shield is fine, but if you choose to do so, why would you wield your sword with one hand lol? It just came off as silly. I wasn't fond of Gregor's choice of flimsy as **** helmet either. Remember how Gregor exploited an improperly-affixed helmet/gorget in his first appearance? Well gee...
For that matter, Oberyn being able to so easily parry and block Gregor's blows in of itself was a bit problematic (In the books, he never parried Gregor, the one time they actually "clashed" he was sent sprawling and nearly died), for reasons Backfire said in the other thread. Gregor popping Oberyn's skull like I popped your mother's cherry comes across as odd due to this.
It wasn't a very good fight. GoT frankly tends to not have particularly good fight scenes, but this fight didn't hold up nearly so well as Ned vs. Jaime, Drogo vs. random brown guy, Jorah vs. other random brown guy, or even Gregor vs. Sandor. Which is a damn shame because the Oberyn vs. Gregor fight was meant to be more climactic than all of them.