I am assuming that you mean that you rewired so that they could be plugged into a wall socket and did not have to be hard wired in??? If you are confident that you did this correctly, used the right gauge/type of wire, that you connected the correct wires together, and used wire nuts or some other secure method of connecting your wires (not just black tape) then you should be okay.
I took a couple of 150W HPS yard lights and separated them from their ballasts, ran some longer wires, added an electrical outlet and put them into a cool tube. Four 100W HPS will not put out as much light (lumens) as a single 400W HPS, but they will do you better than CFLs.