I use mine a lot. Even when you don't have your own homegrown harvest to process, you can make some delicious stuff.
If you see pineapple, melon or bananas reduced or just at a good price, they make amazing dried fruit for cereal, baking or just snacking. Home dried apple is amazing - nothing like shop bought. Pears are wonderful, even bulk bag supermarket ones transform into sweet, intense lovliness. Just dip anything that will discolour into lemon juice and water before drying. Using fruit juices like orange or pineapple adds another dimension and the cheapest carton stuff is fine.
You can also make some seriously good flavouring ingredients. Mushrooms dried and put through the food processor make a great powder. I've done this with basic white mushrooms that were reduced and its good, but was gifted puffball powder recently and am happily experimenting with that. Homemade onion and garlic powder are also great. Streets ahead of anything you could buy. Tomato powder is handy to have on hand as well.
Buy one with a temperature control if you can. Herbs need around 40 degrees C, veg 50, fruit 55.