Ranked in these QuestionsQuestion Ranking
Pro Open source
Ardour is open source, so it can be downloaded and modified without restriction.
Pro Compatible with Linux, Windows 7/8.1/10 and macOS
Ardour is cross-platform and works on Windows & macOS.
Pro Clean linear interface
Pro Linux version has JACK support
On Linux, you can use JACK to freely route audio and MIDI to and from other software as hardware.
Pro Multi-display support
Pro Free version with minimal limitations
Unlike some other DAW's which often limit saving, exporting, or advanced features, Ardour permits you to try all the features for free, with the only limitation being ten minutes of project length maximum.
Pro Inline mixing console
You can view and edit plugins directly from the console's mixing channels.
Con No support for VST plugins for OS X
Plugins can be used on OS X only if they are downloaded in AU format, which is supported.
Con Not user friendly
Ardour is very difficult to install and use.
Con No 'scenes'
Ardour doesn't have 'scenes' like Ableton does (would be very handy for live-preformances).