Subversion vs Fossil
When comparing Subversion vs Fossil, the Slant community recommends Fossil for most people. In the question“What are the best version control systems?” Fossil is ranked 3rd while Subversion is ranked 8th. The most important reason people chose Fossil is:
Fossil includes source code management, bug tracking, a wiki, and technotes. It even includes its own web server, though it can fairly easily be incorporated into other webservers.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Clear and simple operation
It has linear history, central repository and management. Lacks too complex features, almost every developer is familiar with it, so everyone knows what to expect and how to work with it.
Pro Binary files handled efficiently
Pro File locking
Pro Incremental revision numbers
Gives you a better indication on how old a specific revision is without needing any more details.
Pro Easy to understand externals
E.g. more easy to understand than Git's submodules.
Pro Free-form versioned metadata
Pro Very complete
Fossil includes source code management, bug tracking, a wiki, and technotes.
It even includes its own web server, though it can fairly easily be incorporated into other webservers.
Pro Self-contained
A Fossil repository is contained in a single file.
Pro Cross-platform
Fossil can run on Linux, Mac, BSD derivatives and on Windows.
Pro Very easy to configure as self-hosted
Single, stand-alone executable, including web server.
Pro Needs very few server resources
Since Fossil is a distributed VCS on top of being a bug tracker, it needs very few server resources.
Cons
Con Branches are hell. Conflicts are hell
Svn is hard to use on multi-topics workflows. Branches exist but are often not used because of the fear of the merge hell.
Also, conflicts are a big deal and happen on the server; it feels like you only have one try and no way to abort/retry your conflict.

Con Underlying model is totally flawed
Need to code in a rural area? Away on a retreat away from a good network connection? On a plane?
Tough luck.
Con Does not forgive errors
Forgot to commit a file, you need to add a new commit.
Con Flawed roll-back
It is nearly impossible to revert a big repository to an older version.
In GIT, on the other hand, this works very well.
Con Only a web interface or CLI
Fossil's bug tracker only works with the web interface or the command-line interface. There's no native GUI client supporting it.
There are some independent GUI clients out there, but none of them support Fossil's full range of abilities.
