Pay with cash or risk them cancelling your contract.
Mistakes happen, but how a company handles them makes the difference.
My experience with Mike Siano (same name as in Siano Appliances) leads me to believe that the company is not an honorable one to do business with. After paying for a purchase with a check and leaving the store, he realized that he had mis-read a price when he wrote a quote for an appliance and ultimately charged me less than his cost.
He called me to tell me that either I would have to come get my check or write another for the difference in price. I reminded him that we had a deal and a signed contract, but his reply was "I'm not going to take a $1000 loss because of this"
I would have gladly chosen to withdraw my offer, but he seemed to think that I was obligated to do so and did not ask for my voluntary withdrawal.
I will not do business with people whom I do not trust and I do not trust Siano Appliances because of this. Cash and Carry from now on.