I would advise someone to order Lanvin in their usual UK size unless their feet are narrow. I am 10us/43cp/9uk/9 Lanvin. I would not size down to a Lanvin 8. I don't know about that, I have a pretty wide feet and I wear a 7 in Lanvin while I wear an 8 in MMM, Raf and CP. Then again I have found that my feet is just plain weird.