I don't think that they had to find an actor who would do a flat out Shatner impression, just someone who would have that Shatner like attitude, movement, and speaking style in general. When SW: episode 1 came out, I was very impressed with the choice of Ewan McGregor as a young version of Obi-wan. You see, for me he fit the mold set by the original actor, and had enough similarities to help me believe (within the context of the storytelling experience) that this was a younger version of the same character. From what I have seen so far, I don’t buy Pine as Kirk. When there was this rumor that Matt Damon was in consideration to play Kirk in this film, I felt he was a good choice and had a good Shatner like quality. I think Zachary Quinto has that Vulcan factor, but will he be a good Spock is still up in the air for me. One of the reasons ST: III is so low on my list of Trek films is solely due to the actress who replaced Kirsty Alley. She was NOTHING like Alley, and I had a hard time accepting the new actress (Robin Curtis) in the same role. I would have rather they just had made her an entirely new Vulcan.