I spent the past week in Audiocodes and Microsoft Lync Training.
I must honestly say I am blown away by these devices.
Key features which peaked my interest:
1. The device has the ability to do Ldap lookups for incoming E1/T1 calls to determine if the user is a Lync user or a PABX user, at which point the incoming call is either routed to the Pabx or Lync Mediation server depending on the outcome of the query.
2. SBA module, this module may appear to just be an SBA, but the unit can in fact support up to two such modules, which is nothing less than a Core i5 or Core2Duo Processor, this could be turned into a full lync frontend server, for example. and perhaps a domain controller onsite, perfect for remote sites requiring minimal hardware on site.
3. Analog, Fax and Generic Sip Phone support with integration into Lync, perfect for scenarios where a typical Lync Phone Edition may not be suited to the job.
This is just 3 points, there are many more, head on over to their website and have a look for yourself.