oh, and with regards to the OP's question:

yes, the difference is definitely worth it.  as i said before, the price of admission is worth it for SSS alone since its a huge boost to any character realism.  but there are many other features like the performance improvements, accurate light falloff modes, a much-improved real-time OpenGL preview that (reasonably) accurately previews your lights in the scene, tablet support for the morph brush (which is getting to be quite awesome, btw), light emitting objects, and apparently hair/cloth improvements - which i havent even touched yet since ive been too busy working on other content.

cheers,

-gabriel