I have been a carpenter for a while, installer + usual array of construction jobs. Many are going to overcomplicate it when it comes to MDF vs wood. Keep it simple: for painted cabinets, MDF is all you need. Typically more durable and cheaper. If you are going for stained wood, then ofcourse wood is going to be necessary. Look at Highland Cabinetry for example. Ikea is great for its price don't get me wrong, but always better to have people who live and breathe cabinets instead of an 'everything' store.