Minus some recastings (Kid Gohan, Kid Goku, Bulma, Frieza, & a lot of secondary & tertiary characters voiced by Chris Sabat in Z) because of actor/actress availability in the intervening years prior to 2009, all of the main voice actors returned to reprise their roles & they sound GREAT! Sean Schemmel especially, since he now gets Goku's character completely. Personally, I DO wish that they reanimated everything from the ground up, but I understand why they did it as they did. If you wanna get someone into the franchise, this is definitely the way. Still, it's much better than FUNimation's remasters, I'll tell ya that.
This series was properly remastered frame-by-frame in Japan for High Definition airings & releases in its original 4:3 aspect ratio, minus The Final Chapters, which was done by a different team several years after the first part finished airing.
Terrible color correction, terrible remastering all around, really, plus cropping the show to 16:9, leaving us who want to enjoy the show as it was produced out of luck unless we track down the Dragon Boxes, which are LONG out of print & expensive on sites like eBay. If you didn't know, Z has some of the most horrendous home releases I've ever seen. This is also the version of Z to get for excellent home releases. Some are simply trace jobs, while the others are completely new. Though there ARE a few redrawn scenes to replace damaged frames. It leads to a faster-paced storyline that's been streamlined a bit for many fans of Z. It has every piece of canon material from the manga, with some short filler either due to animation from the original Z being unable to be changed, or the staff leaving some in for whatever reason that could've been removed, but didn't. If you also prefer the manga, or just hate the majority of DBZ's slow-paced extra segments, or worthless filler episodes, This is the version to watch. Dragon Ball Z Kai is an excellent recut of the original Z for everyone who enjoys them some Dragon Ball, especially Z.