I use the same DMT 325 for Everything. I see no need to spend unnecessary funds. I do scrub it well under running water and liquid dish soap quite often and with some Bar Keepers Friend and some liquid dish soap every once in awhile to clean it up/it will accumulate swarf/at least in my experience.
I've actually considered buying the DMT 600 as a 'step-up' from the 325 and before the 1K level/it would have come in handy for this project. While I've never tried it, the 600 'might also' be useful for sharpening kitchen knives.