Totally agree with this. I own a Integra that shares the same seat frames as some EVO's. People say the Integra is a bone shaker, and poor for long distances but it's simply not correct. I recently drove a 7 hour round trip taking my gf from Manchester to London airport with no back pain, and only very slight stiffness after standing up (you get that sitting on a chair in your house for 3 hours!). This is even with after-market lowered seat rail, i'm 37 btw.
Indeed, infact since this revelation that really its seat frame that makes the difference several leading executive car services have cancelled leases on expensive S and E Class Mercedes and are moving to Honda Civic FD2's instead and Audi is said to be considering the future of the A8, given an A2 with the correct seat frame offers identical long distance ability.
Alternatively it could be all about relativity, do the same trip in a Vectra VXR (It hurts me to praise this car it really does) and you'll notice a difference.