Originally Posted by wrk101

Realize the bb is usually a lot higher on a MTB, so the same frame size will be quite a bit taller.

Put me in the half way club. I traditionally rode an 18 inch mtb, tried a 19 inch, it was too big. Meanwhile, on road bikes, I ride about a 22 inch frame. My latest MTB drop bar conversion was a 20 inch frame size, "half way" between my traditional mtb size and road bike size.