British/Commonwealth M4A1?

[Porkmann]

Hello Gentlemen,  this is my first post after getting the elbow over on TMP in October! 

Can someone tell me if there is any difference between a USA M4A1 and one used by the British / South African armies?  I am specifically interested in vehicles used in the Italian Theatre.  The tank will be painted in the black/tan two tone scheme.  I will be using the excellent model from Blitzkrieg with a Bolt Action commander.  Incidentally, did the South Africans wear berets?

I hope that someone can point me in the right direction as I really am an ignoramus when it comes to non-Ostfront subjects!

My ZA combatant relatives were from WW1 not 2 so I have a dearth of knowledge.

Thank you.