Hi,
It really depends upon the era you want to depict. If you want to do an early Sherman V (the Canadian and British designation for an M4A4) from 1st Canadian Tank Brigade in Sicily and Southern Italy, you would need that narrow M34 mantlet. For a Sherman V from 4th Canadian Armoured Division in NWE, or one from 5th Canadian Armoured Division in Italy, you're pretty much good to go with the Dragon kit. Looking on the web at pics of the Dragon kit I don't see a British/Canadian No. 19 antenna pot/frame.
The figures they appear to supply however are not really suitable. Some Canadian crews had US helmets in Italy, but it wasn't too common. Save the figures for a US Sherman.
Here's a link to helpful tips for building Dragon Shermans:
http://paulbudzik.com/tools-techniqu...struction.html
Hope this helps.
Bill Inglee