Firstly I'd like to say the service through James's sight is 2nd to none. He is an all around good dude. The recoating price seems very good also....and his turnaround time is unreal! No kidding....within days vs. weeks with the factory.
However, I cannon verify the durability of duracoat, though have heard good things about his work.
Now as far as SA's armory coat....it's better than the factory finish. It's more of a deep black color, and seems to be much harder if that makes sense. I have not experienced any rust with it of any kind...but it does not resist scratching very well. I'm not sure if it's just the sharper edges on the Xd or what...it may be the mistake of usin a Fobus holster. After only two holsterings(is that a word?) it left the same scratches across the edges of the top of the slide. I do not use the Fobus very often at all. I only use it while driving...I've got my old Fobus rigged to under the dash.
With leather I've recieved no futher markings tho.
Hope that helps!