100% no questions asked, cordless. The comments about power and run time are amusing...I don’t think the naysayers have used one of these new saws with modern batteries. Crazy powerful, unbelievable runtime (esp. considering the power), and cordless freedom. The modern batteries have a much longer life too. Good brands with solid pack technologies can easily last over a decade and still chug right along. Cordless all the way. You will not miss your old corded saw. They’re that good.
When I had to demolish a 50'x60' metal building I became an expert on Sawzall's. I would be cutting all day long. I would use my corded Milwaukee with either a wood blade or metal blade with my cordless set up with the opposite blade to do a few cuts so as not having to change blades. Having to pull around a 10 gauge extension cord was not the easiest thing to do but there is no way you can use cordless hours on end unless you have a lot of batteries. Some of the places I had to work would have been dangerous if a battery died 1/2 way through cutting up a truss.