Hello, welcome to the forums. Solid HP Endmill by definitionion is a High Performance endmill - that has special geometry that allows it to remove higher amount of material per pass. HP endmills are never general purpose endmills. So yeah HP Endmill is a rougher, but not every rougher is a HP Endmill. Many general purpose roughers can not be used as HP endmills. As a rule of thumb you should not use HP Endmill tool type inside my calc unless your tool manufacturer advertises it as such. The major difference between solid endmill and solid HP Endmill is that later can remove twice the amount of material per pass, its depth of cut is twice of the normal. So, I intentionally did not put word "rougher" in there. You should only use HP Endmill when you know it is one. For all other tools Generic Solid Endmill works just fine whether the tool is roughing or not. Hope this helps.