Jsujo, yes.. risky to upgrade to the H-1A without schematics. But a good tech can always change the factory pc to something exotic and have the circuit board resoldered with lead-free, 4% silver solder. These tweaks will help. But if you're set on an H-1A, I have a lonely unit not in use.
I have two of the "Class A" models in mono right now, using the XLRs... sounds pretty darn good. :-)