The Designer 1 machines have no cooling fan on the motherboard. There was a problem with the motherboard's burning out. Depending on the use, I wouldn't buy it if you're going to have it turned on for several hours each time you use it. If you'll be turning it on and off, the motherboard will have time to cool and you won't have trouble.
But if you're someone who sews all day you should pass on the Designer 1.