Saija's Journal: Learning path and wich BSD for a Developer?

I'm a software developer with 7 years experience, i've used various languages, ides and tools in my career and also have used many operating systems starting with windows 3.11(for workgroups) to windows 7, hp-ux and linux(mandrake, suse, redhat, ubuntu, debian and currently mint), all of this OS usage has been as a hobby and work. Right now i'm tempted to the BSD side, with this i want to know this OS, know the differences, the better and worse thing compared to linux and maybe ditch linux to something totally different, i'm by no means a linux power user but i know how to install software, search the net for the tricky parts(compiling some source, edit random config files, troubleshoot some weird error in the OS, etc) and i'm making this change so i can learn something new and add some new skills to my belt.I'm planning to run the version you could sugest me on a virtualbox vm and from there make the gradual switch at home(there's dual booting on *BSD ala linux+windows?).