American Turn-Key Fabricators interview questions

I got a tour in their nice plant, they asked me a lot of questions, then they gave me a solidworks work test. It seems like they were very happy with me and gave an offer right there. I asked them to send me a firmer offer by email and they offer me to try one thay to work with them to try out. They supposed to do send the offer with on the next day and confirm what day I was supposed to go and try. Next day was silence and for three days it was not contact from them. Then, I tried to contact them for three days with no answer at all. Suddenly days later, day call me if I want to try out without any formal offer. And off course I said not going any more.