Awesome! That is my dream. I was considering getting the 11" 5.56, but found a 9" Bren 2 S, so got that first since the S are rare. Do you think its worth it to have both? I would have gotten the 5.56 first if there were all MS models.
See how you like that S version first. If it blows your skirt up and you're really enjoying it then yes, a 5.56 gun would be a logical step. Its going to recoil less and will be easier to shoot if that matters to you.
IF you enjoy your bren 2 and you find the recoil impulse workable then I would say "meh" to the 5.56 unless you want to convert to bren 2's as being your primary platform of choice. I dont really find the bren to be "better" than a quality AR15, its just different. I originally thought that the bren would be my grail rifle since it offers quite a bit:
Full ambi
Side charging handle
Piston for suppressor use
Folding stock
My actual experiences are proving different. The 9 inch 7.62X39 is over gassed and does not have a suppressor setting on the gas block. The safety is stiff and way less easy to operate than my AR15's. I really dont like how stiff it is when it comes to putting the gun back on safe.
These are all minor quibbles and I very much like the gun. I'm excited to see it evolve but its not the grail gun that I thought it was.