Record
Cost: $1.99 (NOTE: Since I wrote this post and it went live, Polar Bear Farms dropped the price of Record to nothing -- so it's now free, although I don't know how long that will last)

Recording:
Record, formerly Dictaphone (a trademark, which forced the developers to change the name), was the only app to implement a "shake to start a new recording" feature. That's handy, since Record drops you into whatever screen you were last in when you left, and the "new recording" button is one of those tiny plus signs -- harder to hit than Recorder or VoiceNotes.

I like the fact that you can pause the recording, and the VU meter works well. Once you're done, you save the memo. If you don't save with a title, it uses the time/date as a title. I found Record to be pretty quick when starting up, which makes for a fast grab of your audio.

Playback:
Unfortunately, of all the apps I tested Record had the most problems with volume on the recording. Granted, my 1st-gen iPhone and recording using the built-in (as opposed to the headphone mic) didn't help, but I found volume to be lower than the other apps. The fidelity is on par with Recorder and VoiceNotes. It also provides an easy method for scrubbing, with the usual scrub bar.

Sync:
Record uses an app called Sink to, well, sync. The good part is that with one click you transfer all your audio notes. The bad part is there's some setup required, plus we're talking about another app in your system. First you set up the desktop app by naming your machine, then you go into Record and start sync. You'll get a PIN to enter on the Mac side, and you're ready. You only have to do this once, thankfully. Once audio is in the Sink app, you have to select each audio file and go to File > Export to get it out of Sink. Files are saved as .aifc files.

Bottom line:
The killer feature of Record is speed and ease-of-use. With a fast launch time and shake-to-record, it's certainly got some advantage. But if you record a lot of small clips, the real killer comes in file organization. There's a smart folder option that'll automatically populate folders based on titles. So, labeling audio with the word "idea" in there will drop those into an idea folder (as you can see in the gallery). Unfortunately, those folders don't translate to the SInk app! The saving grace of Sink might be integration with Polar Bear Farms' other app, Notes, but I haven't tested that yet. At $1.99, I'm not sure this app gives you the value of the other apps, even with smart folders or speed. (Again, it is now free, so Record may have pulled ahead of the pack)

iDicto
Cost: $.99

Recording:
iDicto uses a tiny plus sign in the upper right corner to begin recording. While not impossible to hit one-handed, it isn't as easy as every other app in this review. Once you hit the plus, you still have to move to the bottom of the screen to begin recording. Then, while you are treated to a simulated reel-to-reel tape recorder, you don't have any feedback on audio levels. That said, iDicto was the only app with preferences in the Settings app, so you can change the recording quality. The options are 8kHz, 22.05kHz (default, and typical of the other apps), and 44.1kHz. The only recording mode I've used is 22kHz, and that's the sample clip included in this review.

Playback:
Tapping on a clip in the list views starts playing the clip immediately. There's a scrub bar up top, but at the bottom of the screen there's rewind/play/ffwd and volume controls. While this provides more controls than most of the apps, it also increases the confusion level. I don't understand why the UI splits up functions so much, but once you're used to it there's a certain method to the madness. While you can sort clips by Name, Date, Icon or Priority (there are a bunch of crazy icons to choose), I'm not sure people will find use for this. I guess if you're sorting stuff like grocery lists, random thoughts, etc. the icons make sense, but I find it's just another feature thrown in for feature's sake.

Sync:
Sync functionality is identical to Recorder, but the implementation on the iPhone is confusing. You have to go to the recording screen to sync, for no apparent reason at all. Also, if you have wifi turned off, every time you launch the app you'll get a warning dialog. That's one more click between you and recording audio, which is bad. Clips are saved as .caf files. The one shining feature is Bonjour support, which means you can save a little typing and browse Safari's bookmarks to get to the sync going.

Bottom line:
iDicto is loaded with features, but the question is will you use them? At $.99 and with the option for higher-quality recordings, this might be the app for organization freaks or concert bootleggers.

VoiceNotes
Cost: Free!

Recording:
Standard quality, plus a nice, big "Quick Voice Note" button on the main screen. There's also a plus sign to start recording. The difference is that the quick button starts recording immediately, leaving you to name the recording later. The plus sign opens the recording screen, but the button is green, waiting to be pressed and start recording.

Playback:
The UI for VoiceNotes is simple and functional, but that drops a few features. There is no volume adjustment, no scrub bar, just a list of recordings and a play button next to each item. There is a search feature, and an edit feature (to change titles), but otherwise it's all pretty basic. That's not a bad thing, but something to consider. The quality of the recordings seems to be about like the rest, although it's almost as quiet as Record, and not as strong as Recorder.

Sync:
VoiceNotes uses a Java app for Windows and Macs, although you'll have to decide on 1.5 or 1.6 of Java for your Mac. I thought I had 1.6, but apparently I didn't. Once the 1.5 version was installed (and it has an installer requiring admin access, unlike Sink, which is drag-and-drop) the app worked fine. You can start or stop the sync server, and downloads can save wherever you like. The most unfortunate part about the app is that it is a rather clunky Java app. As you can see in the gallery, choosing a different download folder is a pain. It doesn't look or function like a Mac app. If you're willing to put up with the non-standard nature of a Java app, you'll be fine. Everything else works great and doesn't require as much setup as some other sync options. Audio downloads as .caf files, just like iDicto.

Bottom line:
The app is free! So there's that. It's actually quite robust, and it was the first app I used for recording audio. I went to a bluegrass festival and felt comfortable grabbing quick clips, syncing those to my Mac, and using them in a slideshow. I think for anyone looking for a cheap fix, this will likely fit the bill.

Final thoughts:
If you're looking to spend $.99 on something that suits most needs, get Recorder. It syncs most gracefully, and provides quick recording. If you need smart organization, and want something that looks nice, get Record. iDicto is probably useful for categorization, but it felt clunky and was missing features like visual feedback on levels while recording. Still, the possibility of CD-quality recording is a plus. VoiceNotes is free, but sync was slightly clunky to set up and wasn't as nicely designed as the others. Check out the gallery to see the differences between the apps in action.

Here are the App Store links for each app:
Recorder
Record
iDicto
VoiceNotes

And here are the audio samples for each app (right-click to download, as .caf files won't play in your browser, but the AIFF's might):
Recorder
Record
iDicto
VoiceNotes