Our Review:

Installation: Ninja Download Manager has a clean installer with no adware. Just accept the license agreement, choose installation folder, shortcuts, desktop icon and it's finished. A welcome screen pops up, showing release notes, and how to integrate with Chrome and Firefox browsers by downloading the extensions. Although Opera support is not offered out of the box, with Download Chrome extension for Opera, you could install Ninja extension for Chrome on Opera. Un-installation went fine although I had to manually remove the extensions.

Interface:  Ninja has a modern, compact and trendy interface. You can add, edit and access various download queues from the bottom. The download sessions: all, finished and pending ones are neatly arranged across tabs. Hovering your mouse on the start and stop buttons gives you an innovative way to start and stop downloads across various queues. The settings, site logins, media downloader all floats into view from the right when accessed, keeping the interface components compact and clean. Speed indicator is also shown on the interface. I wish it supported skinning/themes. And also I wished the floating window was more useful.

Features:  For a relatively new software product, Ninja is packed with a lot of features. It's the only free and stable download manager currently that supports download queues with a scheduler. Since it uses sequential writing technique, you can preview incomplete audio and video files while downloading. Moreover the media file can be converted to different formats after download. Speed limiter is available for every download queue, and even each download, so you can still keep using internet while downloading. A powerful shredder is built-in which will completely remove all traces and meta-data of downloaded files when necessary. It's one of the few DM's that supports refreshing expired links. Sites Manager lets you keep track of website logins.

Usability:  Ninja, for now only supports Chrome and Firefox, and can be tweaked to support Opera. Its media downloader is independent of the browser, and while it has certain advantages, it does take a lot of time to scan the media files on webpage and doesn't detect media on many sites. It doesn't provide download categories out of the box, but you can add various categories manually. Also I couldn't find how to export/import downloads and settings. Ninja misses an option to check the downloaded files by an antivirus. But overall Ninja is still a top notch download manager.

Support/Updates:  Ninja is the fastest growing download manager. It's releasing updates frequently and the developer heeds to most user requests and feedbacks. Currently watching the development stage gives me every reason to be happy about. You may post your ideas or feedbacks to the developer here and the forum uses a voting technique to see the most popular ideas. Quite creative!