I liked Ninja Storm.
I dragged myself through Dino Thunder's season.
SPD/Mystic Force/Operation Overdrive/Jungle Fury-- From what little I saw or could tolerate to watch they looked terrible. Overdrive's OP theme was utter crap.
I guess you could say I got a little jaded opinion because I went and watched all the Japanese versions and they all looked and sounded superior.
RPM- I actually got through a few episodes. Liked the Go-Onger nod.