I'm only really familiar with the first four films (Planet...to Conquest....) but I though they were all good films. If the sequels didn't quite match up to the original (a tough call), they certainly didn't disgrace it. I found 'Beneath...' a little bit boring in places, but full of good ideas and interesting concepts. I like 'Escape....' somewhat more, not least because of the very clever way they thought up to extend the franchise. The government conspiracy angle is chilling and the way the mood of the film shifts is very well-managed. The downer ending does make me a bit angry, though. I presume that the 'bad guy' was meant to be a satire on Henry Kissinger? 'Conquest....' I remember as another good, and unexpectedly violent film. You certainly root for the apes! 'Battle..' I only saw once, when I was very young and I don't recall it that well. I remember enjoying it, but suspect time has not been kind to it. Roddy MacDowell was a tremendously charismatic lead figure for this series. He was also great in the sadly short-lived tv series (playing a 'same-but-different' character) which I saw before the film series.