If it's anything like it's older brother in Buffalo, Millennium Force will not let up until it hits the brakes. Plus, I don't know of any coaster that only goes 50mph after a 180' hill with a head of steam. It'll probably be close to 65-70 on the drop into the island.
Remember coasters are not engineered to stay at top speed for the entire course. Physics won't allow it. So to compensate, everything is made smaller, closer, etc. to give the illusion of speed and power. Yes it's gonna be slower at the end, but what coaster isn't? I don't think we'll disappointed with the fact that it's only going a measly 50mph a few feet off the ground towards the end :)
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Scott W. Short
sshort@mediaone.net
http://welcome.to/midwestcoastercentral