The storyline starts off with a intriguing premise, and the overall plot was satisfactory, but the character of Dr. Elizabeth Weir was vastly changed in the process.
Weir's character made mistakes that the Weir we know certainly would not have done (i.e. Take the easy path to ascension through "digital ascension", trick the Atlantis team into letting other replicators come), all in all an otherwise satisfactory episode was ruined because her character was not properly written for. I can see why Torri Higginson declined the offer to return to the show since this Elizabeth Weir was not the character she portrayed for the last four years.
On the positive side the actress portraying Weir, Michelle Morgan, did a spot on imitation of Weir. The voice, the posture, the mannerisms, they were all deeply reminiscent of Weir and I was thoroughly impressed. I recommend this episode just to watch her portrayal of Dr. Weir.
The ending leaves rooms for the return of Weir and her cadre of peaceful replicators. I sincerely hope they return and that the writers create a faithful portrayal of her character in the future rather than the let down that was this episode.