My 2005 odyssey doesn't have rails but today I went to purchase the whispbar S17 with K303 footpack for my 2005 japanese honda odyssey (NZ market).
The Prorack booklets state that the S17 & K303 will fit MPV oddyseys from 2004 through to 09.
Upon fitting these to the car, I started to note that they wouldn't secure properly. The odyssey door posts have an unusual angle that makes it extremely difficult for the footpacks to grip to and pull against. When tightening the footpack grips they would just start to slide off once getting tight.
I was with a prorack expert who has fitted thousands of roof racks to cars and this had him stumped. We went to the mounting instructions and follwed these precisely to exact mounting measurements and no luck.
I think this is why we're hearing that the odysseys are not compatible with proracks whispbars. In this case, they simply couldn't be mounted. Gutted! Coz the Whispbars are very nice.