I'm late to the party on this discussion, but I've had great support and success with Ericsson-LG eMG100 platform. I've been with them since the LDK days and we have a lot of these systems running in small offices. We also have enterprise edition vUCP's and cloud instances of vUCP. I've installed as few as 4 or 5 extensions with SIP and CO lines. The support is excellent and the product is great quality.