I'll take a swing at the hornet's nest!
I've enjoyed the sound quality of pretty much every DAP I've listened to. There probably isn't a bad one out there. I own a 5th generation iPod, which I like, and have heard lots of others at meets. I can't speak to the build quality/durability of all of them, but the iPod has held up fine.
That being said, DAPs are consumer goods (I know there's an exception or two) and they're not in the same league as nice DACs, CD players or turntables, especially when coupled with a quality amp. I don't have high expectations for DAPs since they're more or less disposable. Wait a year and another one with more capacity, UI upgrades, etc. will come along.
No, I'm not crapping on them. I just got back from a vacation where my rig was the iPod and my e3cs. Not as good as my full-sized open headphones and tube amps or my speakers.
But it is good enough.
That point seems to be lost on a lot of people who wrap their personal identity around the gear they own and the corporate image of the manufacturer. I like my iPod, but am pretty sure I would have enjoyed my music just as much with a Cowon, Sansa, Zune, et al. It's like the burrito truck where I can get a good asada burrito for $3.50. Not fine cuisine, but the $3.50 burrito makes me happy and the guy in the truck is nice, too.
So get the DAP that appeals to you and don't worry about whether you have the "best" one. Enjoy it for what it is and put more attention on the home headphone and/or speaker rig. That's where the money pays off. But like I said, I was out on a deck chair with the iPod and e3cs and was plenty happy.