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So I am wondering, what is there about ubl that would make it more desireable over bilinear and how can it be done as automagically as possible?
Probably the single best reason is the integration between the G26 Mesh Validation and the G29 P4 R interactive mesh editing. If an area of the mesh needs to be tweaked slightly to be perfect, you will know it and can do it very quickly.
Other than that.... both Bi-Linear and UBL are built on a mesh bed leveling foundation. With an accurate mesh, both should give you good results.