I'm sorry, but I'm gonna have to say SOB is going to be the better of the two coasters. I think it provides a little more intreging design than Millennium Force.
After 5 years, I think Millennium Force will out-do SOB for smoothness sake. I'm not saying that SOB will be extremely rough, but you have to consider, woodies do get rough through time. It's just a fact of nature, unless PKI knows something no one else does! :)
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