How can such potential customers follow up?

A potential customer, just useful to our company's products, after my telephone appointment, the other party very readily promised me to visit, I took the sample door-to-door, in the process of visiting the two sides are quite happy, and the other side of the procurement of my samples are also very satisfied, and asked me to leave samples for their testing. And told me the specs and purchases they used in the company, Let me give you a quote. I passed the quotation the next day, the other side said look first, later contact me, after about a week, the other party did not return my words,, I called the past, the other side said the unit price is no problem. At present, the boss is checking it out. Have always been polite ... But I'm looking at the side that their company is really in a rush to replace the existing supplier of the product ... Tell me, is it true that their boss is in the review?