I thought the first 2 seasons were good, but only for the younger audience. I rewatched it a year ago, and I didn't enjoy it as much as I thought I would.
Now, back then, I watched season 3. When I was young, I didn't like it too much, and I only got up to a certain point in the season. However, I rewatched it back in gr 12, and it was honestly the best digimon series I've watched thus far. The atmosphere was a tad bit darker, and I thought it played with my sympathies and emotions a bit more. I also ruined it a bit by analyzing the series like I would with an academic piece of literature (metaphors, symbolisms, tone, mood etc), and I found that it actually enhanced the experience, rather than ruin it like it did for a few other shows. I'm currently rewatching one episode at a time. Season 4 and 5 were brutal. Not touching season 6.