When comparing spectrwm vs bspwm, the Slant community recommends bspwm for most people. In the question“What are the best window managers for Linux?” bspwm is ranked 9th while spectrwm is ranked 10th. The most important reason people chose bspwm is:
It has a low footprint.
Ranked in these QuestionsQuestion Ranking
Pro like Xmonad light
Spectrwm behaves largely like Xmonad (which is a good thing) without the ~700 MB GHC dependency and with plain text config files
Pro Has a plain-text config file that it can reload while it's running
The config file can be reloaded while the WM is running, allowing the user to see the results of editing the config without logging out and back in again.
Pro Sane defaults
Inspired by xmonad and dwm, spectrwm has defaults that any normal user would enjoy rather than using an odd language or asymmetric window layouts.
Contains a basic set of options and doesn't require a language to configure it.
Pro Great for beginners
The defaults, simple design, and plain text config file make spectrwm a fantastic WM for those who aren't that familiar with Haskell, for example, and who just wish to get something substantial up and running.
Pro Supports floating windows
Spectrwm offers built-in keyboard shortcut support for floating windows.
Pro Very lightweight
It has a low footprint.
Pro Drag&drop / Mouse support for resize/move
You can resize, switch panes, and resize tiles via the mouse.
Pro Very flexible
The keyboard shortcut are handled by another module so it's easy to use other inputs. The configuration is also simple.
Pro Based on binary space partitioning
The windows tiling is handled as the leaves of a full binary tree. This makes it easy to partition as you like.
Pro Open Source
Pro Live configuration updates
No need to restart for updating configurations.
Con Difficult to master
It does take time to learn the ins and outs of all that can be changed by editing the configs. It can also take some time to finally attain a configuration that is perfect.
Con Poorly documented
Compared to something like i3 for example, a user following through i3's documentation is basically guaranteed to get a working desktop suited to their needs. Setting up bspwm is much more of a headache due to developers assuming things are clearer than they are.
Con Lacks transparency support
Like most window managers there is no built in compositing, which means no transparencies.