I can see how on paper people may think that way, however, my vote goes to Vanessa Downing, as well. This is not to say that I do not think that Debra Lawerence is not talented, she just does not represent my Pippa, the one I grew up watching from the beginning. I think that some of this is down to Vanessa Downing skills as a performer and also the writing as others have mentioned Pippa was written differently following the re-cast, this imho did not help. I can remember Pippa 2 giving Steven a hard time when Sally was missing, and also not being as supportive as I believe Pippa would have been when Dodge returned and I can remember not only me, but my family thinking that the Vanessa Downing version of Pippa would never have treated the victim that way. Then when Vinnie Patterson was first introduced to the series as Justine's boy friend, Pippa 2 treated him like a criminal when he wanted to hide his CD player at Summer Bay House, as his father's property was being repossessed, it seemed very off for any version of Pippa to be judging a young person based on their parent's behavior, then there was the treatment of Jack Wilson in relation to Michael's accidental death. I really think that Vanessa Downing's performances of Pippa were excellent, but I also believe that the character was written better back then. Suggesting that fans should like the actor who played the role longer seems a little unusual, does that automatically make Tobey Maguire the best Spider-Man? Does that mean no one else can come near Sean Connery as Bond? I do not think you are comparing oranges with oranges when you talk about two different actors portraying Roo, one actor in Justine Clarke portrayed a Youth, a high school Student. Georgie Parker was cast in the role of Roo as a mature aged person, over twenty years after Justine Clarke's Roo as a young woman left both Summer Bay and the Series. In that time more than twenty year period, Roo never made a return. It is like saying why does no one compare the Child that Plays Bruce Wayne in the flashback of any Batman film with the actor portraying Bruce Wayne/ Batman in the same film. Like Roo, they are taking on a very different version of the character. Pippa2 immediately followed Vanessa Downing at the same point in Pippa's life as where Vanessa Downing left off playing the role.
