This is a great way to gain money with experience, more efficient than spending experience to reduce the cost of cards. Usually when a card upgrade reduces resource cost, it will cost 1 XP to reduce the cost of a card by 1, but that only helps you if you draw the card, and only if you want to play the card at that time, and even if you do draw the card it may take you a long time to do so. With Another Day, while it costs 1.5 XP per resource, it gives you those resources always rather than sometimes, and it gives you them right at the start when you tend to need them most, rather than at some random later time that may be too late.
In general it is better to purchase this card than to upgrade your Emergency Caches into Hot Streaks. However, if you are really a glutton for money even at the cost of actions, and you need it throughout the mission rather than up front, you may be better off getting Hot Streak in addition to Emergency Cache, to bypass the limit of only two Emergency Cache in your deck. Hot Streak could also be better for certain specialty decks, like those which make special use of events, or fast drawing decks which are certain to run through the entire deck before the end of the mission.