We saved what photographically, was the best stop of our of our epic seven day, 2200 mile jaunt to Arizona and Utah for last, and it was definitely worth the wait.
I've been to Upper Antelope Canyon before, but after having going to the Lower Canyon, really have no need to ever go back. Not that it's not a visually stunning canyon, but it's turned into a Disneyland for photographers, and I don't mean that in a good way.
If you have a DSLR (or an SLR for those who still shoot film) and a tripod, you can drive right to the lower canyon in your own vehicle, pay your $26, and purchase the "Photographer's Tour." For that price, you have two hours to basically shoot on your own, to your heart's content. Another plus, for me, anyway is, I find the lower canyon to be the more photogenic of the two.