Well, with the assistance of deksawyer, I now know that I am not a size 10/44 in Daytona boots.
Now just need to find a good secondhand pair of size 43 Daytona roadstar or similar.
If I buy Clarks shoes I have the widest 8.5 as they offer different widths. Both my Daytona boots are 44 yet the Rainbow GTX boots are a lot tighter than the Journey XCR. The 44 only defines the length, not the width and depth which is more important in my case. So, you may need a 44 in other Daytona models...