There should be an easy way to add global option sets as proxy classes. Currently when you generate a salesorderdetail or quotedetail or opportunityproduct as a proxy class, each one contains its own value for the GlobalOptionSet called eProductType (note that we use CRM Project services).

In order for me to create an interface to work with all 3 entities and the Product Type field, i first need to replace the enum in each file with the generic version that I created outside of each file. Then i can apply an interface that exposes this field when working with generic functions. Doing this however, makes updating the proxy class a pain since its just going to override my changes and revert back to the original enum usage per file.