Why You Need This
Um - let's see. If you really like music and record sound in any way for any reason you would find this little gadget useful in some way at some time. Pretty general huh? Alright - let's get into exactly why this thing deserves your $200.
1) Line In - in as many words you can make your own mp3s from any sound source you have available as long as you can funnel that signal into a stereo 1/8 jack. And it's not just mp3 files that you can create here - you can record what's coming in as .wav files also (for serious high-quality archiving).
2) Stereo and Surround Sound mics: The mics on this unit are really quite something. I've used the Zoom H2 for interviews and on a number of acoustic guitar recordings and what surprised me the most was just how good the voices and instruments sounded even when we didn't take time to think about things like relative volume, distance and the like. The 4 microphones onboard this unit really can record an entire room with surprising separation and detail at pretty much any volume (this can really come in handy when recording a practice session or gig).
3) USB interface - while, admittedly, this writer hasn't really explored the use of the Zoom H2 as a USB mic for recording directly into a P.C. or Mac the fact that this option is available is definitely another value-added feature. When connected to a computer with a mini-USB cord the unit doesn't require battery or A/C power (this can be an excellent 'standby' solution if your batteries go down and you don't have access to a power outlet but do happen to have a laptop handy). You can also handily transfer files using the same USB connection (but you have to choose between archiving and interfacing when you initially connect).
The Bottom Line
In this 'age of the podcast' this unit's a no-brainer-must-have item. The fact that you can effortlessly record a universe of sound, the multitude of editing features built in, the superb sonic results and the price itself make this a clear winner.
13 additional points:
1. if you're using the auto rec feature you can't use a sample rate greater than 44.1
2. if you're recording at a level less than 44.1 you won't be able to use the Normalize feature
3. editing takes about 10x more time than doing the same thing in audacity
4. editing also drains batteries
5. get at least one extra memory card
6. if you're recording only voice it's better to go with MONO
7. try to eliminate noise at the source where possible
8. having said that - room noise can be taken out after the fact in Audacity
9. monitor your levels ahead of time using the monitor feature
10. effects can be added in audacity
11. silences can be added in audacity
12. as long as you record everything to a click track it'll be much easier to line tracks up later
13. never throw away a good performance because it's too quiet