I've been looking at putting an Ultimate seat on my 2017 F3L. The stock seat has to go. I am 5' 10 1/2" tall and in position 4 with short reach bars. This set up with the stock seat is in a comfortable position so I am leaning towards the mid-rider and the passenger area is fairly small as it is and I think the tall-rider will make it that much smaller. For those of you who have the Ultimate seat which one are you using? Thanks Wayne