Good points. The FontPark fonts are legal to use, as far as I can tell, and I really don't think they vary much from the Kindle. I've used them on a Kobo Touch and a Sony 350, and they both look great. The Kindle definitely renders the text better, but I think that is due more to Amazon having better rendering software.

I'm not sure how he can sideload fonts to the Nook Touch anyway as it does not natively support that feature without jailbreaking. He might try embedding fonts in his ePubs, but I'm not familiar with the Nook so I don't know whether it would use them.