The Priority 600 that I ordered arrived yesterday (Labor Day). I was so excited that I started the assembly right away, but after installing the handlebars, front wheel, and seat, I noticed that the bicycle was big and high when I straddled it. They shipped a Large (21"), which is the wrong size. I specifically ordered a Medium (19"). Needless to say, I had to disassemble and repack the bike into the box that it came in. I was so disappointed.
One thing I can say about Priority Bicycles, their customer service is excellent. I texted and emailed them about the situation and they responded the same day, which I was not expecting since it was Labor Day.
So, they are shipping a replacement. Let's hope it is the correct size.