[Brent Hutto]

To answer your question briefly, yes I believe $100 for a classical guitar would be a waste of money...for me.

Longer version. I've played some $100-$200 steel string guitars that, if you want to strum chords and you don't mind a 1-11/16" (or smaller) nut width, were quite cheerful and fun to play. I did an extensive search locally for a $200-class nylon string guitar and there was nothing cheerful about them. Eventually I found one that would play in turn with itself up the neck but it sound approximately like plucking a piece of nylon fishing line stretched between your hands, no "guitar" sound or variation in tone possible. But most of them just weren't playable anyway and if they had any sustain and resonance at all it was only on the wound strings.

Now let me qualify that opinion by saying that I've never played a guitar through a pickup (other than a Strat or a Tele I mean) so obviously if you're shopping the acoustic/electric end of the market your requirements and taste might be totally out of sync with mine. But for trying to make a sound like a classical guitar acoustically I just don't think it can be done for $100 or even twice that much.

I'll make one other comment prefaced by a totally sincere With All Due Respect...

I've discovered that all cheap guitars are a waste of money for me. As long as I have one good guitar for the type of music I'm playing at the moment (steel-string fingerstyle, classical, what have you) I could have 20 crummy guitars sitting around and I'd never pick one up for more than five minutes. I can't play much but for better or worse my ear is attuned to hearing a nice, resonant and expressive guitar tone. Even if only 5% of the time my playing is "right" I don't want to waste that moment on a dead-sounding guitar. If what floats my boat were some sort of strumming or picking style there may well be inexpensive guitars that sound great but for my kind of fingerstyle I've never seen one. Just one hacker's experience but there it is.