Reegar said:

Is this series watchable for an adult who never encountered it as a child? I mean, I'll watch the old TMNT series from the late 80's-early 90's, but it's great for reasons rooted in nostalgia. I don't know if I could sit down and get into it otherwise.

Meh.

It is interesting to watch for historical purposes. And to check out the production design, vehicles, and character designs. The plot is somewhat interesting. Especially the first 4 episodes.

But the screenplay is very Saturday Morning-ish. The dialog can really dial up the corny to 11. Especially the C3P0 slapstick.