I am 6'3" and I get my length from torso.
I own the Caldera Niagara (Geneva's sibling) and it fits me great! The raised platform in the middle also makes the spa fit well for the 5' tall Wifey!
I do not know that if it is due to height or design, but the neck jets in the "Ectasy" seat really do not do a lot for me. Perhaps other Caldera owners can comment further on this one?
Jeff