Heres pics of the MMS117 head on a DX10 body. The jacket is also from MMS117 (and yes I know its missing a silver stud on the collar)
and DX10 shades:
Now, I didn't actually secure the head onto the neck. Its only sitting atop it with the neck pushed up into it a little and friction holding it on. However I'm 90% certain a balljoint would make it fully compatible. As I mentioned previously though its a tight fit, making movement maybe a bit more restricted and liable to cause marks or paintrubs on the neck.
I had taken comparison pics alongside a figure with the MMS117 head on its own body but to be honest the pics didn't really show up the difference.
It looks great and if you bought one of the new Arnie TT coming out in a month the neck ball joint should work for the hs.