I would say, for razors that will need a lot of work (restoration more than honing) you could set a pre-bevel on the 325 and then go to the Norton 4k to set the bevel. I wouldn't call the "edge" off a DMT325 a "set bevel," though.

On razors that don't need restoration, you should skip the 325 all together, though. Setting the bevel on the 4k is not ideal, but it can be done. I have to agree that getting a 1k will be very helpful it you plan on setting bevels.