Woohoo- the chips are in - much to my surprise, they just left them on my doorstep - guess no signature needed (yikes).
added this hi-res scan (thanks FJohnson)




Hey folks - my artwork is signed off, and the chips are nearing production.
Here is the proof page:
My thanks to FJohnson, and the rest of the forum for all the input. In the end, you can see I went back to non-denoms.
HPC was great to work with - if you want to do your own artwork - I suggest that you start everything off in Adobe Illustrator - or whatever your preferred vector art progam is. I ended up recreating everything sans the ambigrams in AI at the end.
Note: Had I not done most this legwork myself, given that each chip is a separate design, I was looking at $800 in fees. My actual amount was far less. So - if you are looking to do a full custom set (like these, or say the current American Beauties set in creation), definitely consider tapping your friendly neighbor graphic designer to help out - to minimize the pain. (Also, make use of Adobe's 30 day trial versions of software - that allowed me to do all the work, and never actually purchase any software).
By wish of the ambigram artist, these chips will not be reorderable, nor will be permit anyone else to use the ambigrams in this manner, as the community is trying to keep the art from being commercially exploited. I respect his wishes, and am glad at least he supported my making these for myself.