Seiko: Sumo or save up for a Marine Master?

This is only an impulse. Only.😀

The impulse is for a Marine Master if truth be told but the lesser Sumo pops up as a possible option.
I really ought to clear the "watches to sell box" first and probably will, making this a slow acquisition rather than buy-it-tomorrow.
Without dwelling on the exact difference in price, is the MM really worth so much more than the Sumo?
I am not about to flip any of my existing divers so I need to justify making room for another dive watch.

The size and bulk of the mm300 particularly on the bracelet is something to think about as is the "return to Japan" for service thing. Yes...there is/was some guy in the states who could do it. Haven't heard about him in a while. I like the one piece case though. And I do like wearing the thing on a nato, but find myself switching out with the bracelet a little more than I maybe should but what are drilled lug holes for if not to make it easy and clean for changes? Between the two and not being able to have both and given other divers in the case I would take the mm300 and find myself torn between bracelet and nato. Too many words. Sorry.

have fun
kfw


Edit: clarity