There are no brakes on MF other than the final run. And with or without it, you won't break 100mph on MF. Time to summon Mr. Physics (TM):
v(f)^2 = v(i)^2 + 2gd.
Convert everything to metric, of course.
v(i) = 0 (you have no vertical velocity at the top of the hill)
g = 9.8 m/s^2
d ~= 91.5 m (300 ft)
v(f) = your velocity after you've fallen a distance of d, in this case, your speed at the bottom of the drop
Your fastest possible ride, assuming you've refitted MF with frictionless track and wheels and moved it into a vacuum, is a little over 95mph. If you want to claim that the hill gives you an initial velocity, then let v(i) ~= 5.8 m/s (13 mph, the lift hill speed). Now you can get it to 96.5mph. But that's definitely it, unless you have a neat way of bending space-time while you ride. Since friction and freefall air resistance play a small role on the actual ride, trim off a few mph. There's the touted 92mph in all the papers.
But of course, ask the Lemon Chill guy, too. Whatever he says, it's ALWAYS right :) Who said physics was an exact science anyway?