The name of the device sounds somewhat like a disease doesn't it?
Well I did buy it around swine flu panic season.
This unit is pretty much the single most handy bit of kit I've ever owned.
The mics are pretty good, it's battery powered, takes line and guitar level plus has phantom power(don't expect your batteries to last if you're running a Rode Nt2a).
I use it all the time from recording my daughter's growls in the bath to (you guessed it) recording instruments.
Instead of going through the process of booting my PC and loading plugins, with the H4n I'm off and taking musical notes in seconds. Half the time I just sit it on my lap and record the unplugged guitar sound.
Nice and easy for the times when you've got your groove on, but probably not going to remember every little riff.
That's me pretty much every time I play... Well the times my mojo is in gear anyway.
The H4n doubles as an FX unit and Triples as a USB interface.
Zoom is known for it's long history of effects units, I think the first one I played with was a 9001 back when I was in highschool(wasn't mine). The effects models in this unit are ok. Nothing amazing, but they will get you some amp models and phase effects with a minimum of wires. Think of the fx as a bonus chocolate served with your latte.
The USB interface was touted as USB2, but it really is not any better than a usb1.1 device.
On all three of my computers(all quite powerful windows machines FYI), the latency is so bad that you can't monitor your playing in real time. It's ok if you plan to monitor off your input, but forget about enjoying any onboard effects or using guitar rig in real time. Latency aside, it is a great feature to have if you're wanting to play along to more than four tracks.
I got my unit from USA when our currency was strong and the locals were selling it for double the price, and that includes shipping from the USA. I'd like to see the USB section updated for a future release. It's not essential, but if I was to purchase the unit for playing real time, I would be disappointed. As it is I have an excellent MAudio delta1010lt PCI card that has near zero lag.
Another thing to be aware of is the power supply. It's switchmode and on Australian power points, it generates a bit of a high pitched whine. This could be taken care of with a little filtering and it's not that big of a deal since the unit runs for ages on batteries if you don't plan on using phantom power.