Ive kind of never understood this either...............What is wrong with the cast iron original equipment?
Seems to me and Ive had my Akorn for years and my Akorn Jr for two years now that the cast iron grate is rock solid and after a high heat clean look pretty damn good after years of use. Personally I like the center insert so I can add whatever during the cook like wood chunks or lump or maybe even stir the lump around after it gets going.
And yes I can get great grill marks on my steaks....
the beauty of the Akorn is that it is cheap and does everything a BGE can do but more efficiently.....you start adding expensive parts to it and it doesn't make any sense anymore