Can anyone tell me what Fitflop sizing is like please? I've got my eye on some toe post sandals in the sale. I'm a 5.5 and often find in Clarks and Skechers sandals, toe post styles with no ankle straps, that a 5 is fine - otherwise I seem to lots of the insole showing round my foot iyswim, which I'm not keen on. I like the Gracie styles and the ordinary flip flops. TIA