coming back to the topic, i think pki wouldn't benefit from a 4D coaster...look at the terrain. SFMM is nearly flat and X sits on totally level land. sure, there is some level land for such a coaster, but i think pki should use the hills, creeks and valleys it has if they do build a new coaster.
i'll admit ive never even been to SFMM therefore i haven't ridden any of their coasters. i won't say that X is rough, but if arrow hasn't done something to make it's rides smoother, i would probably just ride it once for the fact that it's a one-of-a-kind coaster and not because it gives a nice comfy ride.
i'll stick to my guns and say that if pki does get a coaster in 2005 (im betting so) that they should either get a 250+ foot B&M hyper or (if they really had the huge bucks) a sweet intamin giga.
this way, it would be MUCH easier to incorporate the awesome terrain they have at the park (look at The Beast and Adventure Express).