Depending on how many more elite dungeons I clear today (looking at one, possibly two more shard refreshes), I could hit four hundred Mythril today.
Seeing as I have not pulled many times (thinking four x11s, a few singles near launch to get started and one each $1 pull), I am really excited to get a massive shot in the arm in terms of gear. Up until the XIII event, I only had one soul break, Kain's, which wasn't immensely useful (powerful for sure, but compared to the utility of Sazh's, my second, it didn't do me many favors). That's mostly just a tip that 3★ and 4★ isn't "trash" if used properly (expand inventory, keep it all, combine when possible, abuse synergy).
My current plan (as posted before) is one x11 on each celebration banner, which will leave me with one-fifty. From here I guess I could pull multiples on something, out of the banner list the one with Tyro and Firion's items would be the one I would throw the dice at. Or I could just save for future event banners. My only good MAG weapon is a 4★ (or a 3★+?).
Seeing as I'll need space for all them 3★ and 4★, I'll probably pump my inventory to 300 with the next event Mytril (been doing one +5 each fifth day "daily bonus" Mythril since launch, so I'm at 255 now).
I'm also thinking of making sure I have enough to do five or ten refreshes on the orb event, but there's enough time from here to there that I shouldn't need to bank anything today.