First of all, yes, this is a "one trick pony". However, this is a pony that Apple, and iTunes should do a much, much better job with than they do. So... as someone who makes a lot of mixes, burns CDs for people, and listens to a lot of music, $30 isn't so bad.
I LOVED version 1.0, but I dinged the DEV in a review here when 2.0 came out, because of the "turn on soundcheck" function. Apparently when the 4th gen iPods came out, they closed the "loophole" the dev was using, so he had to go that route.
So now this version has come out, and at first I was VERY skeptical about plunking for more $$. However, I downloaded the demo, and.. lo-and-behold... it IS re-built from the ground up. The interface is much improved, and it now has the ability to process many songs at once. Yay. It also produces much better results than 2.0. And while still not perfect, it's still better than iTunes "stock" soundcheck.
A couple of features that need a'implimentin':
• A PAUSE button
• Some way of dealing with "no tag" songs. ...updating the tags in iTunes only fixes a scant few of these. More songs than you'd think do NOT have the proper tags.
• Some way of dealing with iTunes AAC protected songs, and podcasts.
Otherwise, a worthy update. A step forward. Stable, fast, and pretty too.