Is no faster then the other apps.
Is not being faster than other apps a bad thing about my app? When two things perform equal, how can one be worse than the other, because of performing equally?

It's searching capabilities are poor and when it does find something it doesn't bring you straight to the item. instead you have to navigate through the folder paths to the item.
You should try the list-view, it helps...

Since it doesn't allow you to browse a disc at all
Have you bothered to even try? The ReadMe clearly states how to browse through a volume's contents...

it doesn't even show you what other items are in a folder with the item you searched for.
I see this as normal behaviour. If i search for an item, other item's are not supposed to show up! that would render the search function useless, wouldnt it?

With DiskTracker you can grab a folder right out of DT and drag it to a different disc or sever volume (as long as the disk is mounted).
And with this app, you have to doubleclick on an item to have it openend in the finder, so you can copy it from there...

I'm really not sure what this app would be useful for. DT has all kind of useful features missing from Media Catalog. You dont happen to be DT's PR person, do you ;-) As far as i am concerned, your post holds little to no ground, nor does it contain any constructive criticism.