Assuming that you were to use 5 park days this trip and the remaining park days on a later trip, you might want to compare the cost of a 10-day no-expiry vs 2 5-day expiry passes.
In that case the 10-day adult no-expiry MYW base pass would run $431.33 with no discounts. Two 5-day adult expiry MYW base passes would be $585.76. Assuming that prices DO NOT go up between now and the next time you use your tickets, your savings would be over $150 per person.
But if you consider that buying those 10-day passes ties up a big chunk of money for a few years, you may want to get the 5-day passes.
Then there's the possibility that they may get misplaced or even lost between trips.
Or, you may find that Disney offers a package deal that is too tempting to pass up except that you already have money tied up in partially-used 10-day passes.
The best deals can usually be gotten thru the MouseSavers newletter link. But every once in a while, other ticketbrokers will put certain passes on sale, so you need to keep an eye on all of them.