Being using ImageOptim all this time, can see the different with Optimage. Brilliant!!!
Favorite use cases are to strip out metadata (location stuff usually), and get mockups ready for decks so that it doesn't take forever to load.
The developer is friendly and open for requests. In fact he already had a list of new features (including some of which I was asking for) for upcoming releases that he compiled from the suggestions of other users of the application.
It took me a while to decide and shell out some money since I've been using ImageOptim (F/LOSS, donationware) for quite some time and it served me well, but on my tests Optimage was a clear winner on all fronts: final quality, compression ratio, speed, features.
Totally love the app and hope It goes well so we can have Optimage for a long time :)