This is a real importnat point.
I ride a 56 x 56 Guerciotti road bike. I t fits like a glove.
I bought a 56 x 56 Guerciotti Cross frame - which is a mile too big.
The bottom bracket height is a full 1.5 cm higher and the big over-sized top tube raises the standover even more.
Standover hits 85 cm - like the Ridley.
Gotta pay attention to the the BB height or the othe stuff doesn't matter.
I now have a Guerciotti frame and fork I can't use - too big.