Loose powder and compact powder get talked about like they're the same product in two packagings. They're not quite — the finish and how they wear through the day is a little different, and which one you want depends on what you're using it for.
Loose powder
Finer texture, generally gives a more natural, skin-like finish. It's the better choice for setting makeup in the morning since it doesn't sit as heavily on top of foundation. The tradeoff is it's messier to carry around and reapply on the go — not something you want to be doing in your bag on a bus.
Compact powder
Pressed, more portable, easier to touch up with mid-day without making a mess. The finish tends to be a little more matte and buildable, which is useful if you're dealing with oil through the afternoon rather than setting a full face in the morning.
So which one do you actually need?
If you're only using powder once a day to set your makeup before leaving the house, loose powder does that job better. If you know you'll need to touch up during the day — long work hours, humidity, an event that runs late — a compact is the more practical carry option. A lot of people end up owning both for exactly this reason: loose powder at the vanity, compact in the bag.
Medora's compact and loose powders come in matching natural, beige, peach, suntan, and brown velvet shades, so switching between the two doesn't mean re-matching your shade from scratch. See the full range here.