There are less expensive dehydrator brands out there but if you want to seriously get into dehydrating as a way of preserving and storing food I'd go for an Excalibur. I used to have one of the smaller less expensive models. They're good for trying out dehydrating and making a few snacks but f you want to dehydrate a bushel of apples that you pick up on sale at a farmers market or do a whole 10 pound bag of potatoes you'll need the Excalibur. The other models aren't large enough and it would literally take a week to dry all those apples or potatoes. For this reason I'd also recommend getting the 9 tray Excalibur instead I'd the 4 tray model if you can afford it.
I've been trying out tons of different foods in the dehydrator and so far I'm pretty impressed. You can eat the foods dry themselves or rehydrate them to use in meals. When you dehydrate the food the texture is never the same as fresh but that's okay if your using them in stews, soups etc.. To rehydrated them I boil the dried food for a few minutes. You can also steam your veggies to rehydrate them.
(Above: dried tomato, red /green peppers, celery, mushrooms, broccoli, potatoes and my assistant)
The dried peppers in my homemade salsa are pretty good. The potatoes are excellent pan fried or in a stew but they're too thick and slimy mashed. Rehydrated apples in an apple crisp are also really good. Tomatoes come out soft but are good for soups. As for broccoli, the stems get too tough so just dehydrate the tops. I haven't done onions or garlic yet because supposedly they really stink up the house and it's too cold to open the windows to ventilate.
My general idea is to buy veggies on sale and dehydrate them so they'll last a long time. I got a bunch of mason jars for my birthday and bought oxygen absorbers from that Canadian supplier I mentioned above. If I put the dried food in the jars with the O2 absorber it should last at least a year though various sources claim they'll last up to 5 even 30 years! Personally 5 years seems the limit to me and after 2 years I'd be wary.
The website Dehydrate 2 Store is a great resource with tons of recipies, tips and how-too videos. The book "The Dehydrator Bible" also has a lot of great tips and recipes which is where I found my recipe for apple crisp.
I'm learning that there are a lot of different methods and recommendations out there so if you want to get into dehydrating try different things and have fun experimenting!