GekiRanger for me so far is... awesome. It has a great story, possibly one of the best and most consistent stories of the decade for Super Sentai so far.The characters leave a bit to be desired but the history behind the Kensei and Kenma is attracive, as is the possibility of a connection between Jan & Rio. But ultimately, the main reason I'm enjoying GekiRanger is because it's sticking to the point with each and every episode (7 & 8 barely withstanding): the physical, mental, and emotional growth and development of practitioners of two varying forms of the same martial art.
Den-O on the other hand... uh... I agree with the notion of the two franchises switching roles this year. Whereas Geki is holding my interest, Den-O has already lost mine. The characters were fun for the 1st few episodes, but by the time more Imajin started appearing for the good guys, I had already gotten sick of seeing Hana beat the crap out of Momotaros, of the constant attempts by Ozaki and Miura to court Airi, and seeing the antics of the Taros constantly possessing Ryoutaro and getting him into trouble. But by the time Ryuutaros arrived, I had already determined to stop watching Den-O. Although I like seeing a healthy mix of action and comedy in my toku, I made that decision because of what it lacks the most: a gripping plot keeping the two balanced.
Den-O's forms are cool, I will give it that, but Zeronos hasn't caught my attention too well. And with the appearances of Sieg, Wing Form, and Ga-O, all supposedly movie exclusives, as well as the early arrival of Climax Form, I'm convinced that the writers' attempt to use the previously mentioned appearances to promote the movie is also shooting the movie in the foot by taking away the excitement of seeing the movie. I'm also convinced that this is a sign that the writers have run out of ideas far too early. With Kamen Rider's ratings slumping year after year since 2004, this is something that Toei and Bandai don't need.