I used a 24V 450W bed on a printer and would never do that again. Go with line power switched by an SSR. The SSR won't need a heat sink and you won't have to worry about burning up your PCB or MOSFETs with the high current that a 24V bed will need. Add an electrical fuse and a TCO for safety.
Ultra MegaMax Dominator 3D printer: [
drmrehorst.blogspot.com]