I have Adobe Camera Raw set to output a 16 bit 300 dpi Pro Photo RGB file. Back in the day I would set the print size and let Photoshop determine the dpi accordingly. For my typical 44 inch wide print this worked out to about 150 dpi. Now I let the printing utility supplied with my large format Canon printer (Pro 4100) do the resizing automatically. FWIW I'm pretty fussy and am unable to tell the difference in sharpness and detail when comparing the old and new prints. Others' results may varry......
