When comparing Growl vs Quicksilver, the Slant community recommends Quicksilver for most people. In the question“What are the best power user tools for macOS?” Quicksilver is ranked 11th while Growl is ranked 18th.
Ranked in these QuestionsQuestion Ranking
Pro Support for a lot more applications than the default notification system
In addition to all the applications that other people have written that support Growl, Growl includes several 'Extras' that serve various functions.
Pro Ability to be themed
Growl comes with almost 20 themes pre-installed so you can pick what works best for you. You can also create and install your own custom themes.
Pro Sync with mobile phone via Prowl
Prowl is the Growl client for iOS. Push to your iOS device notifications from your Mac or Windows computer, or from a multitude of apps and services.
Pro A lot more powerful than Spotlight
Pro Makes it really fast to do a lot of actions
There are customizable triggers and capability to execute multilevel commands - e.g. launch terminal app, give the location of script and supply parameters for the script with one command.
Pro Vast extensibility via plugins
A lot of different plugins for browsers, file systems, mail clients, etc.