So no doubt about it Dragon Ball Z is one of the definitive animes for 90's kids. Even if you didn't turn into an anime fan, if you grew up in the 90's you probably watched DRAGON BALL Z. One of the many iconic shows of the 90's but something fans and non-fans can agree on is the pacing is so bad. Both the fandom and hatedom have made jokes about how 10 episodes at a time would just be characters talking, so a recut of the series that cuts down padding and omits the filler should be perfect for everyone right? Wrong apparently. It seems that many viewers prefer the original Dragon Ball Z and a lot of that appears to have to do with the Nostalgia Goggles.
Music: Now whenever an English dub creates its own soundtrack there will be always be a Broken Base
if the original score is better or the Dub Score. Of course for many fans who grew up on the 90's dub hearing the original Japanese soundtrack in Kai is probably off-putting. But even if you don't like the Japanese score is it really a reason to dismiss Kai?
The Voices: Another common criticism I heard is that the voices in Kai are awful. Um what? Most of the voices in Kai are the EXACT same voices as Dragon Ball Z, a few of them have changed such as Frieza. But these are for the better. Which do you prefer Frieza as an old woman doing her best gollum or a Frieza that sounds sinister (and British?!)? If you picked the former, the Nostalgia Goggles are on way too tight.
Censorship- Another complaint is about censorship, now if you're strictly comparing the Japanese versions I can see where this argument is valid, but for the English dub even the Bowderlized Nicktoons version is much less cnesored than Dragon Ball Z in the early days. None of that Another Dimension crap or HFIL. There is also an uncut dub version just like Dragon Ball Z has an uncut dub.
In short Dragon Ball Z Kai is MUCH MUCH better than Dragon Ball Z, and if you prefer DBZ its time to take off the nostalgia goggles.