Ha! I love the discussion. Of all the guitars I've owned, I still think if I had to choose one - based on just "loving to play" factor and not value. I still think I'd choose my Yamaha Nylon string.
Again, this is strictly just for my personal opinion.
Here are my reasons...
1) It's acoustic. I can play it in any situation (other than a very loud situation) - with or without power. Just grab it, sit on the couch and play.
2) It's easy to play. The nylon strings make it very easy to physically play. This means that long after my hand strength starts to fade on other instruments, I'll still be able to play this one.
3) It's a smaller body size. It just fits me better. I'm sure I'd like any sort of parlor size guitar. I just prefer the smaller to larger size guitars. A side note - this also makes it lightweight and easy to carry.
4) Finally, and most importantly, I just enjoy playing it. I can play classical, fingerstyle, jazz and whatever else on it. I can't do bends and distortion on it but that's ok.
I can honestly say, if given a choice of "you can only play electric or acoustic guitars for the rest of your life" I wouldn't even hesitate and gladly walk through the acoustic door grinning.
- Steve