You could also ask the purchasing department, or the person who does the ordering, for a suggestion for a manufacturer, and call the manufacturer. You must decide how you will deal with sales reps. Most researchers consider it to be a real pain to have to talk with one, and many institutions and companies will not let sales reps onto the floors to harass people. Yet a good sales rep can be infinitely helpful. Most are trained in one of the biological sciences, and they can help make decisions and cut costs.
Sales reps have a tough time.
Be courteous to all, but be selective when deciding with whom you will speak. There are several on-line services that enable you to look up any item, compare prices and specifications, and request information from the manufacturer. Several of these are listed in the Resources, at the end of the chapter. You could also go to one of the many Biomedical Science bulletin boards on line, and pose a question about the item in question to people who might have used it. You could also ask sales representatives for help.