Well I just got back from watching the new Den-O movie. Let me tell you, it was pretty much non-stop action. There is one place where it slowed down for about 5 mins, but it picked right back up. I would give it a 9 out of 10.
Decade gets much more screen time during the big final fight. Kiva was a very late addition to Climax Deka, whereas this movie is built around the continuity with the Den-O World episodes of Decade, and Final Countdown. There's things that went unexplained in the TV episodes which are covered here, and vice-versa.