I have a 'portable" Saddlemen Gel pack. It is a life saver for the wife, even with the Sundowner passenger pillon. I've tried it on the front and besides raising me up an inch, I didn't find it really helps at all. But on a long ride, its a nice change (after a while, anything is a nice change). The stock sundowner is really pretty good.
I rented a bike with a stock seat, and boy does that suck after a couple of hours. Any dealer who rents V-rods with stock seats isn't doing sales of V-rods any favors. A guy in Montana who used to work at a dealer said that on several occasions, they got a call from a rental customer who was several hours away saying "come get me - no way am I riding this thing back".