SBP Kelsey Hayes

I have a 70 Duster with 10 in drums. I want to go to disk brakes. Im sure this has been answered many times but couldnt seem to find a difinitive answer. the question is from a functionality perspective, is there any advantage to going to the LBP disk set up over the SBP disk set up? I would prefer to keep the SBP as I have an 8 3/4 rear end with SBP and would like to keep the same rims. I am currently running soild dish 15 in centerlines wich are obviously SBP 5 on 4. So other than wheel selection, are there any other advantages to single piston calipers vs 4 piston? I thought i read that the 4 piston calipers are less reliable. Thank you for any info, always appreciated.