Back in the day, I developed a class module that I could import into VBA-enabled applications (Excel and PI Processbook) that was essentially a wrapper around the PI Win32 API. It allows me to do the stuff like get PI archive or snapshot values etc. This was before the SDK existed.
The class still works fine, and does what I want it to do. However I was wondering if there would be any value at all in updating it to use the SDK instead of the API. I was wondering if fundamentally the SDK is also just a wrapper around the API. I presumed it was, and therefore if my class still works, there is no need / case to update it at all.