Is there a view on what size tool is required? For my Harrison M300, this is a semi beefy home lathe. 12mm almost looks too small. I spoke to Kenny last night (dude selling the stuff) and he says on his Haas CNC lathe, he tried bigger tools (20mm etc) and found that they took up too much space and settled with 16mm. Suppose feeds and speeds are important here too. Most of my turning is alu or softer steels.