Angle grinder vs die grinder vs rotary tool

So basically what the title says, I was doing some digging around for rotary tools (dremmels etc) and angle grinders because I want to start making knives but space is tight and apartment + forging sounds like trouble. As I was looking I cam across the existence of die grinders (¼" spindle instead of ⅛) and did some googling about them. From what I found people said they were basically like the lovechild of an angle grinder and a rotary tool. How accurate would you say this is and more importantly, could I get a die grinder instead of a rotary tool and an angle grinder? Would rotary and hacksaw be good enough instead of an angle grinder or die grinder? The die grinder comes with both a ¼ and ⅛ spindle so I can also use normal rotary tool attachments on them.

Any help/feedback/experience would be very much appreciated