@watchidiot thanks man, appreciate the pictures. Looks like EB 946 is shorter compare to Rain which might work in my advantage. I should take the same size as Rain which is 8UK and hopefully heel slippage won't be the same.
I wear Carmina Inca, Forest and Uetam in 8UK and the fit is perfect. However, Rain in 8UK has a huge heel sleep and a lot of volume (I have low instep and narrow heel).I'm thinking to go with 7.5UK in 946 but will confirm.