I have finally watched some of DragonBall Z Kai, the 2009-11 remake of the DragonBall Z series.
It's a nice remake, in that they cut most (in some cases, all) of the pointless filler material that was added to the original show. The majority of the original show was filler, to the point where every episode of Kai is made up of two to three DBZ episodes, put together.
Why wasn't the original DragonBall Z like this? The show is so much more interesting, with good pacing.
They also retranslated the dialogue in Kai. Now the characters swear a lot more frequently. There are more frequent musical interludes. But at least there aren't five-minute flashbacks in every episode! That's a major plus.