BizTalk Transform API app vs custom API app

Question

I am creating an Azure Logic App, in which we have to migrate millions of records. In the series of apps somewhere in between we need to transform the data to suit the destination.

As the Transform app will accept only XML input and provide XML output, which will be needing JSON conversion, shall I write custom C# code to do the transformation. Which will give better performance.

Answer 1

Why not use XSLT? It is pretty quick. There is no need to use custom c# code for a transformation.