SD and rapid mods (even without using SD for playing) are, right now, which most testers use and newbies are encouraged to use it in order to get the latest version of S44.
Another good reason to use SD is SL’s Bugs. SL authors can defend themselves as much they want but I have not known any version of SL completly free of bugs. Even the latest stable version of SL (the 0.84 at this moment) is known to have bugs. SD has far less bugs.
Rapid mods are automaticaly built with the latest revision of the SVN, so it is the solution we found to play the latest version of S44 ( despite Bugs sometime encountered in these latest versions, lol Flozi changes are now feared ) .
“Stables” releases are very slow to be released, so rapid mods are very usefull now.
There is a python software to get rapid mods : github.com/tvo/rapid/ . May be it is possible to make it works with springlobby ?