Catchy title, eh?

You should bookmark these two links. They are fee calculator pages for UPS and USPS. Generally, all you need to know are the packages' weight, the two zip codes and the packages' dimensions (which you can guess if the package is not gigantic), and Presto!, there are the costs:
http://wwwapps.ups.com/servlet/QCCServlet
HTTP://POSTCALC.USPS.GOV/

Well, I have always thought that the heavier the package, especially at far distances, the better the deal is with UPS. And the commercial-residential thing about UPS is not an important factor at all. Most chip packages are light, so the USPS is better there.

Robert