The answer to this question is that while the MSWINSCK.OCX is a good control for simple single connection clients or servers, it is not designed for, and therefore does not properly handle, many client or server connections. The conceptual model for this control is one connection per control—this means that a server or client that must dynamically handle many connections must use control arrays with the control. There are a number of documented problems with doing this (memory leaks when unloading the control) in addition to the fact that it is a poor programming model, making it unsuitable for heavy duty enterprise level applications (see Microsoft’s Knowledge Base at http://www.microsoft.com for more details on this control).
In contrast, SocketQ was built specifically for the purpose of building high bandwidth network server applications with many client or server connections, and as such has been designed for and uses OS specific optimizations that are specific to this purpose.
This means applications built with SocketQ will have the ability to acheive much higher throughput. Note that there are many features and capabilites that are not available from the MSWINSCK.OCX, such as the ability to listen or connect to a specific network interface, or to retrieve all IP addresses for a local host.