When comparing Howl vs Spacemacs, the Slant community recommends Spacemacs for most people. In the question“What are the best text editors for UNIX-like systems?” Spacemacs is ranked 14th while Howl is ranked 19th. The most important reason people chose Spacemacs is:
Spacemacs is just a well-configured Emacs distribution with community-sourced best in class plugins and layers selected to take the setup pain out of Emacs. Evil mode gives the Vim bindings and modes for fast editing, while Helm makes everything discoverable to make learning to be more productive simple and unintrusive.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Keyboard driven
You don't need the mouse to use Howl. Everything can be accomplished with commands and shortcuts.
Pro Fast startup
It's extremely lightweight, making it start up pretty quickly.
Pro Easy to use
Howl is very intuitive and easy to use.
Pro Easy to extend
Plugins (bundles) can be written in Lua or MoonScript.
Pro UI Focused on editting
Non distracted icons, toolbars, pannels, extra spacing, etc.
Pro Language tooling
Has built-in functionality for completion, inline documentation and linting so IDE-like features can be added easily.
Pro Command line palette
Search for your commands in an easy way and see in the list which key-strokes are mapped to which commands
Pro Open source
Howl is an open source project and is actively developed on GitHub(howl-editor/howl). It has a MIT license.
Pro Works on OpenBSD
Pro Preconfigured emacs distro
Spacemacs is just a well-configured Emacs distribution with community-sourced best in class plugins and layers selected to take the setup pain out of Emacs. Evil mode gives the Vim bindings and modes for fast editing, while Helm makes everything discoverable to make learning to be more productive simple and unintrusive.
Pro VIM Keybindings with EMACS ecosystem
EMACS ecosystem and language support is best in show. The EMACS is a great IDE that was in search of a good text editor. Spacemacs makes EMACS have a good text editor.
Cons
Con Lack of Lua examples
Although Howl can be extended in both Lua and MoonScript, almost all bundles are written in MoonScript. This means that it is a bit harder to find examples if you'd rather write your bundle in Lua. MoonScript can be compiled to Lua but the code won't be as clean and understandable as if it would've been written in Lua by hand.
Con Emacs is slow
Emacs is single threaded which means that if you enable all the great features you might be used to from Vim, it will run noticeably slower which can be quite frustrating at times. There are efforts at a concurrent Emacs, but they don't seem to be going anywhere.