I'm still waiting for my H4n to arrive in the mail (groan). There are lots of examples on the web between the H4n and other recorders, however my choice came down to noise comparison, features and price.
Noise - H4n is a big improvement over H4 and other recorders in that price range. Yes there still is hiss but from my research via web examples, I felt it was the least distracting of the bunch. Some other systems did perform better, but I feel they lacked features I wanted and I felt I could live with the lower quality of sound for those features; you might feel different.
Features - The H4n has a lot of fancy features (I read the most of the manual). Yes its a complex device but there isn't much it can do that the bigger more expensive devices could do (unless you need 4 XLR jacks, etc); for me the 1/4" Balanced Jacks are great as all my current mics currently use that (high fidelity shotgun, high fidelity lav). Things like juice link etc for HDSLR sounded better, but its not a digital recorder.
Price - There are easier nicer audio recorders for around $400-500 dollars. However that is almost twice the cost of the H4n and at the end of the day they don't add any additional features I was going to use. Nicer sound yes, but do they allow you to do something the H4n can't, mostly no (for me anyway). I put that money towards a better XLR shotgun mic which will improve my audio far more than a better recorder at this point.
Gripes - Although I haven't one in my hand, my one issue is there is no cage on the onboard mics. So once I get one I'll do some thick wire bending and build it a small cage so that they don't get whacked (not that I plan on hitting this device, but I've heard the mics are easily damaged).