[Serusers] Which version of SER to use?

We are planning on deploying a couple of SER servers and integrate them with either SEMS or Asterisk for voicemail. However, we are a bit confused as to which version of SER to go with? From what we can tell, the latest stable version is 0.9.6. However, we know of the new 0.10.X version. Reading up on the site, there is some documentation that explains a little bit of the differences and/or migration recommendations/steps. So, in an effort to keep life as simple as possible, which version should we work with? We are afraid that if we go through a learning cycle with 0.9.6 we're going to "suffer" when migrating to the new version, either because of the learning curve or because of a potential painful migration process. Any recommendations? Thanks