Although I have a sink, I have to agree with Ralph... I've never spilt any substantial amount. I occasionly overflow a bottle when filling if I'm not paying attention (thinking about next thing to do usually). My sink has a front higher than the trays and that can be annoying at times, so I reckon you could use a flat top and if your really worried about spills, run a border of 5mm acrylic sheet (say 25mm wide, stuck down with silastic so it has a waterproof seal) around the bench as a backup measure to contain the rare accident (5mm deep by the size of the bench would hold a fair chunk of liquid) while you cleaned it up.

The one caveat to this I can think of, is how are you washing your prints? My sink has a well at the end, which is plumbed, in which I sit my wash tray (for 8x10s) or over it (larger wash tray, which drips into the well). I also use it to wash trays and equipment in.