I'm just under 5'10" (177cm). just over 32 inch real cycling inseam. I spoke with Tony personally, and he put me on the 59cm. And it works beautifully. I think the sizing is essentially stated size minus 3cm to equal other bikes. So the 59cm is really like a 56cm. And this makes sense to me by feel. My 59cm IRO actually feels a bit smaller to me than my 57cm Look road racing bike. Geometry is a weird thing.