I would be concerned if the peak current is waaaaay above the RMS. I'd want to know the duration of the 'peaks'.
You need to be able to supply RMS as well as the peak or you are going to starting popping fuses.
I do feel your pain. In work in a large mfg facility and it's always difficult to determine how much room is left on a bussbar without doing some data logging, field observations, and then some estimation (I hate to use the words 'best guess'). In the end that's what fuses are for.
But like sabrown sez...and unless I missed it in the thread...you'd need to tell us more about the load.
