Temporary items with enough time left become permanent?

What if a temporary item could become permanent if it has over a certain amount of time, like 250 days to a year before it expires? It would probably bring in a lot of revenue for Z8, too. People might buy a temporary coupon item 3 times to get enough days, or spend ~50k ZP on a temporary gun that they want unlimited use of (I personally would love to have the Dual Uzi's, but the chance of getting permanent items from crates is usually too tempting to pass up). Not to mention people would be more inclined to buy temporary items such as hats or sprays if they could get it for keeps. Other temporary items such as ZP grenades or mutation characters would also probably be purchased more if they could be extended to permanent use. From a programming standpoint, it could be checked/updated at the same time that the game checks weapon requirements for ribbons. Thoughts?