Ecco sizing - accurate or go smaller?

They are listed by EU sizes on Snainton which is where I'm looking - it says 43 = 9/9.5, or 44 = 10.
Funnily enough, on Clubhouse they have it listed differently for the same shoe. They say 43 is 9, and 44 is 9.5/10. Which leads me to think the 44 will be best.