Don't get discouraged- the American Harvest round dehydrators from Walmart do a more than adequate job!
Plus, the latest incarnation now has a fan and heat element on the TOP, and it circulates a lot better than the old, bottom element and fan models.
The main drawback is that the trays are ridiculously expensive. I got blessed a few years ago and found the dehydrators- with 4 trays, jerky kit, and fruit roll sheets- for 20 bucks. Bought FOUR of them, and hence had plenty of trays.
I finally burned out one bottom unit (their big drawback was that pieces of stuff you were drying could fall down into the unit), and started using the second one- I just stored the power units on my "extras".
But I found the top powered unit last fall and bought one to try. I now use all my trays with it exclusively.
I'm sure the Excalibur does a more even job, but I dry bushels of tomatoes and apples and other stuff in this with no problems. If I have different sizes and some aren't quite dry when the rest are, I simply sort them onto a separate tray, store the dry stuff and put the rest back in for a few more hours.
I do rotate the trays if/when I check to see how stuff is doing, but I haven't seen that it's really necessary- and it's much LESS necessary with the top mounted fan unit.
I would suggest trying one of these less expensive units until you see how well you like dried food, and how much you use it.
I've gotten to the point where I don't can tomatoes much at all- I dry them all. Sometimes I'll make a couple of pots of soup and can it, but everything else goes in the dehydrator. SO much easier, cooler, cheaper....
Summerthyme