BetterZip for Mac allows you to view, modify, add, and remove files directly from archives without the need to unzip them. This app also features its own implementation of a keychain but unfortunately does not integrate with OS X's keychain and thus cannot be synced over iCloud. Another potential drawback is the lack of Finder integration.
After a straightforward installation, BetterZip for Mac displays a clean and easy-to-understand interface that lets you quickly reveal the contents of archives without having to unzip them first. The transfer speed for files won't disappoint you: it took us a little less than 30 seconds to extract 300MB from a larger archive. One peculiarity of the app is that if you try to view a damaged archive, BetterZip treats it as a password-protected archive instead. The keychain, itself, works well enough, though; we were able to interact with password-protected archives without entering the specific password. However, we were required to set a master password and enter it to confirm our identity. A great feature is the "Clean" option, which scans archives for predetermined and user-defined files and extensions and automatically deletes them.
If you're working with large archives on a regular basis or have to enter complex passwords in order to access archived information, BetterZip for Mac can make your life easier. While this premium app is nothing exceptional, it accomplishes what it sets out to do in a satisfactory manner.
Editors' note: This is a review of the trial version of BetterZip for Mac 2.3.2.