DWalt - sometimes the Buggered up screw Heads can be repaired to look almost as good as new if you have patience , skills and some basic hand tools. The head is gently hammered back into shape, then dressed with a File, Dremel and Arkansas Stone and then re-blued. Slots can be re-cut with a Dremel Cut-off wheel or a Jeweler's Saw Blade.

If some part of the screw head is missing or as you state split - then of course you are just plain out of luck, but if after you replace them all you want to "play", its a great way to perfect this technique.