I have a nesco that I use and use! I just love it...but there are a few things to be aware of up front. The add on trays can get costly..anywhere from 10 to 15 dollars and up a piece...so if you think you might need them, try to buy them in your original set up, they are much cheaper when included, that getting them after.
Some manufacturers, like Excalibur are more expensive up front..but are much more consumer friendly after the sale...they have a toll free number listed on their parts page to call and they will walk you through replacing parts. Nesco...(as I have recently found out)...would NOT sell me a simple fuse, a one dollar pop in part..but offered to "repair" my unit if I sent it to them with postage paid both ways, and $89.99 for the "repair"...I was furious...got the part locally...as I said, I love the unit..but not their after sale support so much!
Nesco is also american harvest and gardenmaster..they are all under one company now.
If you are not sure you will want one for the long haul, get one on ebay used..they are very cheap on there(at least some of the lesser known brands)..the unit may or may not last, but at least you won't have a big investment if you decide dehydrating isn't your thing.