Leo’s core code is always being improved and developed. Unit-testing ensures that the daily commits are as bug-free as possible. Almost all of the time, downloading the most recent nightly snapshot of the development code is going to give you code that is just as stable and much more up-to-date than the most recent latest stable release which most Leonistas would consider already outdated.
If you are just checking Leo out, feel free to use the latest stable release download if it makes you feel more secure, but once you’ve decided to work with Leo on a regular basis, we highly recommend regularly keeping your installation up to date with the most recent nightly snapshot.
To summarize, you may get Leo in three ways: