本物 or 偽者？

I'm sure you noticed the 者 instead of the 物. And you probably know that both are pronounced mono here but 者 is used with people and 物 is used with things.

Well, while working on an update for our main iPhone app (an absolutely shameless plug!), I came across this sentence:

私には本物の若殿様がわかります。
watashi ni wa honmono no wakatono sama ga wakarimasu.
I know which is the real young lord.

The scene is about a smart youngster named Hikoichi being tested by the lord. He must figure out which of five children is the real thing, er... I mean the real person. So I asked Yumi why it shouldn't be 本者 (even though I had never seen it written as such). She gave me one of those "why-are-you-so-stupid-and-why-did-I-marry-you" looks until I explained there was a 偽者 so why not a 本者?! I guess because it is used as an adjective (notice the の), 物 is just fine?

Anyway, just doing a quick search, it seems the internet is flooded by Japanese mixing up the 偽者 with 偽物.

For Example:
ティファニーの本物と偽者の見分け方 (found on Google)

So are they having trouble deciding if a girl is a real girl (as opposed to an android) or if an item the girl bought from a Chinese retailer on Ebay is a fake? Or is an item bought from Tiffany's?

I guess it is just as well there isn't a 本者. And regarding the two nisemono's... if you want to play safe, just write it in katakana: ニセモノ

(Edit: Found this post by a native Japanese speaker who took a whole two minutes to figure out what 本者 was. Seems I wasn't the only one asking the question!)