To tell the truth i was no hoping that much from that episode. I was expected a not so successfull outcome and lots of catching up between the two stargate teams. I was awfully wrong, and for once i took pleasure out of it.
The character dynamic was great on many level. Daniel and Vala really do have a great interaction on screen. Sheperd and Mitchell also did even for a brief time, and i think there is room for some teamwork between the two in a future. But above all it was nice to see McKay and Carter again. The allusion at what happened during the atlantis episode "Grace under pressure" was fine, and McKay was definitely playing out of the past obnoxious or competitive behaviour he had with her. It seems their complementarity is more and more obvious.
On the storyline point of view. The ancient involvment was clever. Though i think the "coming out" of the ancient posing as a hologram was a bit too fast. This asset could have been kept for a while and maybe in a few episodes should the ancient have taken measures against their own.
One of my favorite SG1 episodes so far!