I like it. I prefer
Amon (and
Eamon, and Aemon) but I like
Ammon too.
I'm not sure about how easy it would be to use
Ammon prn. like
Eamon... it seems counterintuitive to me, and I think it would be easier with
Amon (
Ammon makes me want to say AM-on, like the word "am") but if you corrected people they'd probably get it.