MSODREW  Definitely suited my purposes quickly. The interface does need a bit of cleanup, and Save isn't bound to command + s, but in general I can do gain reduction and noise/hiss reduction in just a few clicks. Plus, its free. 5-stars.  
(Version 3.14)

TEMPEL  I searched for a tool that would quickly allow me to measure the time distance between two events in a recorded sound. First I downloaded WaveJelly, which required me to register despite it being free -> I tossed it. Then tried Audacity, whose downloaded dmg file would not mount (open). Finally, I tried this one, which let me get to what I needed. Still, even this program has some annoyances in its usability:

It appears not to follow the most simple Mac UI guidelines, such as:

- Cannot drop a audio file onto the app to open the file.

- Cannot create a selection by first positioning the cursor at one end, then using a Shift-Click to define the other end.

- Once a selection has been made, one cannot simply drag either border to extend the selection, despite the cursor shape suggestion such an action.

- Version information in the Finder's "Info" window is wrong - it doesn't list the actual version number. Makes it difficult for reporting problems, comparing app version, etc.

Dear programmer, please make an effort to follow common Mac guidelines better, and we may have a winner. ;)

Anyways, thanks for making it available for free.  
(Version 3.14)

RODDY MCKAY  WavePad is a potentially useful application and has some good features.

However, the developers have seen fit to treat the Mac version as a poor relation to the Windows one.

The interface face needs upgrading.

Unlike the Windows version, it does not convert to other file formats after editing. This makes it totally useless for my purposes.

I have contacted the developers, twice, to point out these short comings and to mention the fact that I would pay for WavePad if they would make the necessary improvements.

Perhaps they don't need the money or are so busy that they don't have time to reply!   
(Version 3.14)

KAIDOH  I've been searching for a small quick-and-easy audio editor and although WavePad looks promising it's quirks outgun it's benefits. Some occurances:

- First crash a minute after the first launch.

- Space bar does not start and stop playback as in virtually ANY other audio app.

- Working with selections is a pain: extending or diminishing an existing selection seems impossible (so you better select precise on the first attempt)

- And oddest: Using the window scroll bar does not scroll the window as one would expect but does move the playback cursor (and yes, hence destroying an existing selection)

The developer should be a more adherent to the common principles of GUI-design or this app will be nothing more than constant cause for frustration.  
(Version 3.10)

PHILIPZ  Fast enough for me, exactly the features I want (cut/copy/paste) and some filters. best of all, it's free, what more could you want? I'm not complaining...

(5 stars to counter the previous comment)  
(Version 3.10)